Ger, Roman Basic sets for some basic functional equations. (English) Zbl 1530.39017 Aequationes Math. 97, No. 5-6, 1221-1230 (2023). Reviewer: Eszter Gselmann (Debrecen) MSC: 39B22 39B55 PDFBibTeX XMLCite \textit{R. Ger}, Aequationes Math. 97, No. 5--6, 1221--1230 (2023; Zbl 1530.39017) Full Text: DOI OA License
Ger, Roman On alienation of two functional equations of quadratic type. (English) Zbl 1482.39030 Aequationes Math. 95, No. 6, 1169-1180 (2021). Reviewer: Gian Luigi Forti (Milano) MSC: 39B22 PDFBibTeX XMLCite \textit{R. Ger}, Aequationes Math. 95, No. 6, 1169--1180 (2021; Zbl 1482.39030) Full Text: DOI OA License
Ger, Roman Delta-convexity with given weights. (English) Zbl 1471.39019 Ann. Math. Sil. 34, No. 1, 73-80 (2020). Reviewer: James Adedayo Oguntuase (Abeokuta) MSC: 39B62 26A51 26B25 PDFBibTeX XMLCite \textit{R. Ger}, Ann. Math. Sil. 34, No. 1, 73--80 (2020; Zbl 1471.39019) Full Text: DOI OA License
Ger, Roman A short proof of alienation of additivity from quadraticity. (English) Zbl 1478.39026 Tatra Mt. Math. Publ. 74, 57-62 (2019). MSC: 39B52 39B72 PDFBibTeX XMLCite \textit{R. Ger}, Tatra Mt. Math. Publ. 74, 57--62 (2019; Zbl 1478.39026) Full Text: DOI
Ger, Roman On an alternative d’Alembert’s equation. (English) Zbl 1410.39041 Aequationes Math. 93, No. 1, 299-309 (2019). Reviewer: Stefan Czerwik (Łaziska Górne) MSC: 39B52 26A09 PDFBibTeX XMLCite \textit{R. Ger}, Aequationes Math. 93, No. 1, 299--309 (2019; Zbl 1410.39041) Full Text: DOI OA License
Ger, Roman Solving alternative functional equations: what for? (English) Zbl 1413.39048 Ann. Univ. Sci. Budap. Rolando Eötvös, Sect. Comput. 47, 273-283 (2018). Reviewer: Henrik Stetkær (Aarhus) MSC: 39B52 39B55 39B22 PDFBibTeX XMLCite \textit{R. Ger}, Ann. Univ. Sci. Budap. Rolando Eötvös, Sect. Comput. 47, 273--283 (2018; Zbl 1413.39048)
Ger, Roman; Sablik, Maciej Alien functional equations: a selective survey of results. (English) Zbl 1382.39032 Brzdęk, Janusz (ed.) et al., Developments in functional equations and related topics. Selected papers based on the presentations at the 16th international conference on functional equations and inequalities, ICFEI, Będlewo, Poland, May 17–23, 2015. Cham: Springer (ISBN 978-3-319-61731-2/hbk; 978-3-319-61732-9/ebook). Springer Optimization and Its Applications 124, 107-147 (2017). MSC: 39B52 39B22 39B72 PDFBibTeX XMLCite \textit{R. Ger} and \textit{M. Sablik}, Springer Optim. Appl. 124, 107--147 (2017; Zbl 1382.39032) Full Text: DOI
Ger, Roman Fischer-Muszély additivity: a half century story. (English) Zbl 1387.39021 Brzdęk, Janusz (ed.) et al., Developments in functional equations and related topics. Selected papers based on the presentations at the 16th international conference on functional equations and inequalities, ICFEI, Będlewo, Poland, May 17–23, 2015. Cham: Springer (ISBN 978-3-319-61731-2/hbk; 978-3-319-61732-9/ebook). Springer Optimization and Its Applications 124, 71-106 (2017). MSC: 39B52 39B82 PDFBibTeX XMLCite \textit{R. Ger}, Springer Optim. Appl. 124, 71--106 (2017; Zbl 1387.39021) Full Text: DOI
Ger, R. Mazur’s type problem for convexity of higher orders. (English) Zbl 1399.26024 Publ. Math. Debr. 89, No. 3, 347-353 (2016). MSC: 26B25 39B62 46A19 PDFBibTeX XMLCite \textit{R. Ger}, Publ. Math. Debr. 89, No. 3, 347--353 (2016; Zbl 1399.26024) Full Text: DOI
Ger, Roman; Sablik, Maciej A misleading multiplied number of independent variables. (English) Zbl 1359.39012 Grazer Math. Ber. 363, 75-80 (2015). MSC: 39B12 39B22 PDFBibTeX XMLCite \textit{R. Ger} and \textit{M. Sablik}, Grazer Math. Ber. 363, 75--80 (2015; Zbl 1359.39012)
Ger, Roman; Kuczma, Marcin E.; Niemyska, Wanda On two functional equations connected with distributivity of fuzzy implications. (English) Zbl 1354.39015 Commentat. Math. 55, No. 2, 163-169 (2015). Reviewer: Józef Drewniak (Lancut) MSC: 39B22 26E50 PDFBibTeX XMLCite \textit{R. Ger} et al., Commentat. Math. 55, No. 2, 163--169 (2015; Zbl 1354.39015) Full Text: DOI
Ger, Roman Fischer-Muszély functional equation almost everywhere. (English) Zbl 1315.39011 Aequationes Math. 89, No. 1, 207-214 (2015). Reviewer: Maryam Amyari (Mashhad) MSC: 39B52 39B82 PDFBibTeX XMLCite \textit{R. Ger}, Aequationes Math. 89, No. 1, 207--214 (2015; Zbl 1315.39011) Full Text: DOI OA License
Ger, Roman; Sablik, Maciej Errata list for “Mean values for vector valued functions and corresponding functional equations”. (English) Zbl 1315.39012 Commentat. Math. 54, No. 1, 65-66 (2014). MSC: 39B52 26A24 PDFBibTeX XMLCite \textit{R. Ger} and \textit{M. Sablik}, Commentat. Math. 54, No. 1, 65--66 (2014; Zbl 1315.39012)
Ger, Roman The alienation phenomenon and associative rational operations. (English) Zbl 1321.39031 Ann. Math. Sil. 27, 75-88 (2013). MSC: 39B82 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Ann. Math. Sil. 27, 75--88 (2013; Zbl 1321.39031)
Ger, Roman Convexity and the difference property. (English) Zbl 1300.26006 Indag. Math., New Ser. 24, No. 4, 693-699 (2013). Reviewer: Gheorghe Toader (Cluj-Napoca) MSC: 26A51 PDFBibTeX XMLCite \textit{R. Ger}, Indag. Math., New Ser. 24, No. 4, 693--699 (2013; Zbl 1300.26006) Full Text: DOI
Ger, Roman; Sablik, Maciej Mean values for vector valued functions and corresponding functional equations. (English) Zbl 1300.39006 Commentat. Math. 53, No. 2, 355-369 (2013); Errata ibid. 54, No. 1, 65-66 (2014). Reviewer: Jens Schwaiger (Graz) MSC: 39B52 26A24 PDFBibTeX XMLCite \textit{R. Ger} and \textit{M. Sablik}, Commentat. Math. 53, No. 2, 355--369 (2013; Zbl 1300.39006)
Ger, Roman Alienation of additive and logarithmic equations. (English) Zbl 1289.39048 Ann. Univ. Sci. Budap. Rolando Eötvös, Sect. Comput. 40, 269-274 (2013). MSC: 39B52 13J25 PDFBibTeX XMLCite \textit{R. Ger}, Ann. Univ. Sci. Budap. Rolando Eötvös, Sect. Comput. 40, 269--274 (2013; Zbl 1289.39048)
Brzdȩk, Janusz (ed.); Chmieliński, Jacek (ed.); Ciepliński, Krzysztof (ed.); Ger, Roman (ed.); Páles, Zsolt (ed.); Zdun, Marek Cezary (ed.) Recent developments in functional equations and inequalities. Selected topics. Based on the 14th international conference on functional equations and inequalities (ICFEI) dedicated to the memory of Marek Kuczma, Bȩdlewo, Poland, September 11–17, 2011. (English) Zbl 1279.39001 Banach Center Publications 99. Warszawa: Polish Academy of Sciences, Institute of Mathematics (ISBN 978-83-86806-18-8/pbk). 215 p. (2013). MSC: 39-06 39B72 20-06 53-06 52-06 00B25 PDFBibTeX XMLCite \textit{J. Brzdȩk} (ed.) et al., Recent developments in functional equations and inequalities. Selected topics. Based on the 14th international conference on functional equations and inequalities (ICFEI) dedicated to the memory of Marek Kuczma, Bȩdlewo, Poland, September 11--17, 2011. Warszawa: Polish Academy of Sciences, Institute of Mathematics (2013; Zbl 1279.39001) Full Text: Link
Ger, Roman Abstract Pythagorean theorem and corresponding functional equations. (English) Zbl 1313.39034 Tatra Mt. Math. Publ. 55, 67-75 (2013). Reviewer: Eszter Gselmann (Debrecen) MSC: 39B22 PDFBibTeX XMLCite \textit{R. Ger}, Tatra Mt. Math. Publ. 55, 67--75 (2013; Zbl 1313.39034) Full Text: DOI OA License
Fosner, Ajda; Ger, Roman; Gilanyi, Attila; Moslehian, Mohammad Sal On linear functional equations and completeness of normed spaces. (English) Zbl 1282.46021 Banach J. Math. Anal. 7, No. 1, 196-200 (2013). MSC: 46B99 39B82 PDFBibTeX XMLCite \textit{A. Fosner} et al., Banach J. Math. Anal. 7, No. 1, 196--200 (2013; Zbl 1282.46021) Full Text: DOI Euclid
Ger, Roman; Misiewicz, Jolanta; Wesołowski, Jacek The Lukacs theorem and the Olkin-Baker equation. (English) Zbl 06128645 J. Math. Anal. Appl. 399, No. 2, 599-607 (2013). MSC: 62-XX 39-XX PDFBibTeX XMLCite \textit{R. Ger} et al., J. Math. Anal. Appl. 399, No. 2, 599--607 (2013; Zbl 06128645) Full Text: DOI arXiv
Ger, Roman; Pečarić, Josip On vector Hermite-Hadamard differences controlled by their scalar counterparts. (English) Zbl 1253.26020 Bandle, Catherine (ed.) et al., Inequalities and Applications ’10. Dedicated to the memory of Wolfgang Walter. Selected papers of the 2nd conference on inequalities and applications, Hajdúszoboszló, Hungary, September 19–25, 2010. Basel: Birkhäuser (ISBN 978-3-0348-0248-2/hbk; 978-3-0348-0249-9/ebook). ISNM. International Series of Numerical Mathematics 161, 165-173 (2012). MSC: 26B25 39B72 39B62 PDFBibTeX XMLCite \textit{R. Ger} and \textit{J. Pečarić}, ISNM, Int. Ser. Numer. Math. 161, 165--173 (2012; Zbl 1253.26020) Full Text: DOI
Ger, Roman; Kominek, Zygfryd An interplay between Jensen’s and Pexider’s functional equations on semigroups. (English) Zbl 1240.39054 Ann. Univ. Sci. Budap. Rolando Eötvös, Sect. Comput. 35, 107-124 (2011). MSC: 39B52 20M14 PDFBibTeX XMLCite \textit{R. Ger} and \textit{Z. Kominek}, Ann. Univ. Sci. Budap. Rolando Eötvös, Sect. Comput. 35, 107--124 (2011; Zbl 1240.39054)
Ger, Roman Vector convex differences and Hermite-Hadamard type inequalities. (English) Zbl 1234.26053 Filipczak, Małgorzata (ed.) et al., Real functions, density topology and related topics. Dedicated to Professor Władysław Wilczyński on the occasion of his 65th birthday. Łódź: Wydawnictwo Uniwersytetu Łódzkiego (ISBN 978-83-7525-536-2/pbk). 157-164 (2011). MSC: 26D15 26B25 39B72 39B62 PDFBibTeX XMLCite \textit{R. Ger}, in: Real functions, density topology and related topics. Dedicated to Professor Władysław Wilczyński on the occasion of his 65th birthday. Łódź: Wydawnictwo Uniwersytetu Łódzkiego. 157--164 (2011; Zbl 1234.26053)
Ger, Roman; Nikodem, Kazimierz Strongly convex functions of higher order. (English) Zbl 1204.26017 Nonlinear Anal., Theory Methods Appl., Ser. A, Theory Methods 74, No. 2, 661-665 (2011). MSC: 26A51 39B62 PDFBibTeX XMLCite \textit{R. Ger} and \textit{K. Nikodem}, Nonlinear Anal., Theory Methods Appl., Ser. A, Theory Methods 74, No. 2, 661--665 (2011; Zbl 1204.26017) Full Text: DOI
Ger, Roman; Sablik, Maciej Homomorphisms and boundedness in topological groups. (English) Zbl 1215.39027 Aequationes Math. 80, No. 1-2, 119-130 (2010). Reviewer: Mihály Bessenyei (Debrecen) MSC: 39B52 39B62 PDFBibTeX XMLCite \textit{R. Ger} and \textit{M. Sablik}, Aequationes Math. 80, No. 1--2, 119--130 (2010; Zbl 1215.39027) Full Text: DOI OA License
Ger, Roman Additivity and exponentiality are alien to each other. (English) Zbl 1211.39013 Aequationes Math. 80, No. 1-2, 111-118 (2010). Reviewer: Jacek Chmieliński (Kraków) MSC: 39B52 13G05 39B72 PDFBibTeX XMLCite \textit{R. Ger}, Aequationes Math. 80, No. 1--2, 111--118 (2010; Zbl 1211.39013) Full Text: DOI
Ger, Roman; Reich, Ludwig A generalized ring homomorphisms equation. (English) Zbl 1193.39013 Monatsh. Math. 159, No. 3, 225-233 (2010). Reviewer: Andrzej Smajdor (Kraków) MSC: 39B52 PDFBibTeX XMLCite \textit{R. Ger} and \textit{L. Reich}, Monatsh. Math. 159, No. 3, 225--233 (2010; Zbl 1193.39013) Full Text: DOI
Ger, Roman On vector pexider differences controlled by scalar ones. (English) Zbl 1266.39037 Bandle, Catherine (ed.) et al., Inequalities and applications. Proceedings of the conference on inequalities and applications, Noszvaj, Hungary, September 9–15, 2007. Basel: Birkhäuser (ISBN 978-3-7643-8772-3/hbk). ISNM. International Series of Numerical Mathematics 157, 283-290 (2009). MSC: 39B82 39B62 39B52 PDFBibTeX XMLCite \textit{R. Ger}, ISNM, Int. Ser. Numer. Math. 157, 283--290 (2009; Zbl 1266.39037) Full Text: DOI
Ger, Roman On a problem of Roger Cuculière. (English) Zbl 1266.39023 J. Inform. Math. Sci. 1, No. 2-3, 157-163 (2009). MSC: 39B22 39B12 39B52 PDFBibTeX XMLCite \textit{R. Ger}, J. Inform. Math. Sci. 1, No. 2--3, 157--163 (2009; Zbl 1266.39023)
Ger, Roman; Kochanek, Tomasz An inconsistency equation involving means. (English) Zbl 1168.39006 Colloq. Math. 115, No. 1, 87-99 (2009). Reviewer: Borislav Crstici (Timişoara) MSC: 39B22 26A24 PDFBibTeX XMLCite \textit{R. Ger} and \textit{T. Kochanek}, Colloq. Math. 115, No. 1, 87--99 (2009; Zbl 1168.39006) Full Text: DOI
Kuczma, Marek; Choczewski, Bogdan; Ger, Roman Iterative functional equations. Paperback reprint of the hardback edition 1990. (English) Zbl 1141.39023 Encyclopedia of Mathematics and Its Applications 32. Cambridge: Cambridge University Press (ISBN 978-0-521-07034-8/pbk). xiv, 552 p. (2008). MSC: 39B12 39-02 39B22 39B52 39B72 PDFBibTeX XMLCite \textit{M. Kuczma} et al., Iterative functional equations. Paperback reprint of the hardback edition 1990. Cambridge: Cambridge University Press (2008; Zbl 1141.39023)
Domańska, Katarzyna; Ger, Roman Addition formulae with singularities. (English) Zbl 1085.39023 Ann. Math. Sil. 18, 7-20 (2004). MSC: 39B52 39B22 PDFBibTeX XMLCite \textit{K. Domańska} and \textit{R. Ger}, Ann. Math. Sil. 18, 7--20 (2004; Zbl 1085.39023)
Ger, Roman Fischer-Muszély additivity on Abelian groups. (English) Zbl 1066.39024 Ann. Soc. Math. Pol., Ser. I, Commentat. Math. 2004, Spec. Iss., 83-96 (2004). Reviewer: János Aczél (Waterloo/Ontario) MSC: 39B52 39B55 PDFBibTeX XMLCite \textit{R. Ger}, Ann. Soc. Math. Pol., Ser. I, Commentat. Math. 2004, 83--96 (2004; Zbl 1066.39024)
Badora, Roman; Ger, Roman; Páles, Zsolt Additive selections and the stability of the Cauchy functional equation. (English) Zbl 1037.39008 ANZIAM J. 44, No. 3, 323-337 (2003). Reviewer: Szymon Wasowicz (Bielsko-Biała) MSC: 39B62 39B52 54C60 54C65 39B72 39B82 PDFBibTeX XMLCite \textit{R. Badora} et al., ANZIAM J. 44, No. 3, 323--337 (2003; Zbl 1037.39008) Full Text: DOI
Ger, Roman; Nikodem, Kazimierz A characterization of stationary sets for the class of Jensen convex functions. (English) Zbl 1003.39024 Daróczy, Zoltán (ed.) et al., Functional equations–results and advances. Dordrecht: Kluwer Academic Publishers. Adv. Math., Dordr. 3, 25-28 (2002). Reviewer: Borislav Crstici (Timişoara) MSC: 39B62 39B72 26B25 PDFBibTeX XMLCite \textit{R. Ger} and \textit{K. Nikodem}, in: Functional equations---results and advances. Dordrecht: Kluwer Academic Publishers. 25--28 (2002; Zbl 1003.39024)
Badora, Roman; Ger, Roman On some trigonometric functional inequalities. (English) Zbl 1010.39012 Daróczy, Zoltán (ed.) et al., Functional equations–results and advances. Dordrecht: Kluwer Academic Publishers. Adv. Math., Dordr. 3, 3-15 (2002). Reviewer: J.Schwaiger (Graz) MSC: 39B62 39B52 39B82 PDFBibTeX XMLCite \textit{R. Badora} and \textit{R. Ger}, in: Functional equations---results and advances. Dordrecht: Kluwer Academic Publishers. 3--15 (2002; Zbl 1010.39012)
Ger, Roman Ring homomorphisms equation revisited. (English) Zbl 1160.39327 Rocz. Nauk.-Dydakt., Pr. Mat. 17, 101-115 (2000). MSC: 39B52 39B72 PDFBibTeX XMLCite \textit{R. Ger}, Rocz. Nauk.-Dydakt., Pr. Mat. 17, 101--115 (2000; Zbl 1160.39327)
Ger, Roman; Keane, Michael; Misiewicz, Jolanta K. On convolutions and linear combinations of pseudo-isotropic distributions. (English) Zbl 1016.60003 J. Theor. Probab. 13, No. 4, 977-995 (2000). MSC: 60B11 60E07 PDFBibTeX XMLCite \textit{R. Ger} et al., J. Theor. Probab. 13, No. 4, 977--995 (2000; Zbl 1016.60003) Full Text: DOI
Ger, Roman Examples of Ludwig Reich’s mathematical ideas that inspired Polish functional equationists. (English) Zbl 0979.39017 Grazer Math. Ber. 342, 21-40 (2000). Reviewer: János Aczél (Waterloo/Ontario) MSC: 39B82 39-03 01A70 01A60 39B12 39B22 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Grazer Math. Ber. 342, 21--40 (2000; Zbl 0979.39017)
Ger, Roman Orthogonalities in linear spaces and difference operators. (English) Zbl 0970.39021 Aequationes Math. 60, No. 3, 268-282 (2000). Reviewer: Borislav Crstici (Timişoara) MSC: 39B55 39A70 46C05 PDFBibTeX XMLCite \textit{R. Ger}, Aequationes Math. 60, No. 3, 268--282 (2000; Zbl 0970.39021) Full Text: DOI
Ger, Roman; Koclȩga, Barbara Isometries and a generalized Cauchy equation. (English) Zbl 0965.39022 Aequationes Math. 60, No. 1-2, 72-76 (2000). Reviewer: János Aczél (Waterloo/Ontario) MSC: 39B52 39B62 46B04 46B20 PDFBibTeX XMLCite \textit{R. Ger} and \textit{B. Koclȩga}, Aequationes Math. 60, No. 1--2, 72--76 (2000; Zbl 0965.39022) Full Text: DOI
Ger, Roman Iteration groups of functions satisfying a generalized additivity equation. (English) Zbl 0945.39004 Ann. Math. Sil. 13, 131-141 (1999). Reviewer: János Aczél (Waterloo/Ontario) MSC: 39B12 39B22 26A18 PDFBibTeX XMLCite \textit{R. Ger}, Ann. Math. Sil. 13, 131--141 (1999; Zbl 0945.39004)
Chmieliński, Jacek; Ger, Roman On mappings preserving inner product modulo an ideal. (English) Zbl 0938.39025 Arch. Math. 73, No. 3, 186-192 (1999). Reviewer: Zs.Páles (Debrecen) MSC: 39B52 46C05 PDFBibTeX XMLCite \textit{J. Chmieliński} and \textit{R. Ger}, Arch. Math. 73, No. 3, 186--192 (1999; Zbl 0938.39025) Full Text: DOI
Aczél, János; Ger, Roman; Járai, Antal Solution of a functional equation arising from utility that is both separable and additive. (English) Zbl 0930.39019 Proc. Am. Math. Soc. 127, No. 10, 2923-2929 (1999). Reviewer: J.Morawiec (Katowice) MSC: 39B22 91A05 91B16 PDFBibTeX XMLCite \textit{J. Aczél} et al., Proc. Am. Math. Soc. 127, No. 10, 2923--2929 (1999; Zbl 0930.39019) Full Text: DOI
Ger, R.; Volkmann, P. On sums of linear and bounded mappings. (English) Zbl 0960.39012 Abh. Math. Semin. Univ. Hamb. 68, 103-108 (1998). Reviewer: J.Schwaiger (Graz) MSC: 39B82 39B52 PDFBibTeX XMLCite \textit{R. Ger} and \textit{P. Volkmann}, Abh. Math. Semin. Univ. Hamb. 68, 103--108 (1998; Zbl 0960.39012) Full Text: DOI
Ger, Roman On a system of functional equations occurring in projective geometry. (English) Zbl 0927.39011 Rad. Mat. 8(1992), No. 2, 189-200 (1998). MSC: 39B72 51A05 PDFBibTeX XMLCite \textit{R. Ger}, Rad. Mat. 8, No. 2, 189--200 (1998; Zbl 0927.39011)
Ger, Roman On a functional equation related to the problem of characterizing the cross-ratio. (English) Zbl 0927.39008 Rad. Mat. 8(1992), No. 2, 177-188 (1998). MSC: 39B22 51A05 PDFBibTeX XMLCite \textit{R. Ger}, Rad. Mat. 8, No. 2, 177--188 (1998; Zbl 0927.39008)
Ger, Roman On an equation of ring homomorphisms. (English) Zbl 0912.39017 Publ. Math. Debr. 52, No. 3-4, 397-418 (1998). Reviewer: Károly Lajkó (Debrecen) MSC: 39B62 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Publ. Math. Debr. 52, No. 3--4, 397--418 (1998; Zbl 0912.39017)
Alsina, Claudi; Ger, Roman On some inequalities and stability results related to the exponential function. (English) Zbl 0918.39009 J. Inequal. Appl. 2, No. 4, 373-380 (1998). Reviewer: P.Sahoo MSC: 39B72 PDFBibTeX XMLCite \textit{C. Alsina} and \textit{R. Ger}, J. Inequal. Appl. 2, No. 4, 373--380 (1998; Zbl 0918.39009) Full Text: DOI EuDML
Ger, R. A Pexider-type equation in normed linear spaces. (English) Zbl 0908.39009 Sitzungsber., Abt. II, Österr. Akad. Wiss., Math.-Naturwiss. Kl. 206, 291-303 (1997). Reviewer: C.Alsina (Barcelona) MSC: 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Sitzungsber., Abt. II, Österr. Akad. Wiss., Math.-Naturwiss. Kl. 206, 291--303 (1997; Zbl 0908.39009)
Ger, Roman Indexed families of bijections and iterable functions. (English) Zbl 0909.39007 Grazer Math. Ber. 334, 97-104 (1997). Reviewer: M.C.Zdun (Kraków) MSC: 39B12 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Grazer Math. Ber. 334, 97--104 (1997; Zbl 0909.39007)
Ger, Roman; Sikorska, Justyna On the Cauchy equation on spheres. (English) Zbl 0894.39009 Pr. Nauk. Uniw. Śląsk. Katowicach 1665, Ann. Math. Silesianae 11, 89-99 (1997). Reviewer: C.Alsina (Barcelona) MSC: 39B52 39B72 PDFBibTeX XMLCite \textit{R. Ger} and \textit{J. Sikorska}, Pr. Nauk. Uniw. Śląsk. Katowicach, Ann. Math. Silesianae 1665(11), 89--99 (1997; Zbl 0894.39009)
Ger, J.; Ger, R. On some curves in vector lattices. (English) Zbl 0881.46006 Math. Pannonica 8, No. 1, 83-102 (1997). Reviewer: Zoltán Boros (Debrecen) MSC: 46A40 26D07 46B42 26A51 PDFBibTeX XMLCite \textit{J. Ger} and \textit{R. Ger}, Math. Pannonica 8, No. 1, 83--102 (1997; Zbl 0881.46006) Full Text: EuDML
Ger, Roman Delta-exponential mappings in Banach algebras. (English) Zbl 0905.46030 Bandle, C. (ed.) et al., General inequalities 7. 7th international conference, Oberwolfach, Germany, November 13–18, 1995. Proceedings. Basel: Birkhäuser. ISNM, Int. Ser. Numer. Math. 123, 285-296 (1997). MSC: 46G05 39B52 PDFBibTeX XMLCite \textit{R. Ger}, ISNM, Int. Ser. Numer. Math. 123, 285--296 (1997; Zbl 0905.46030)
Ger, Roman; Semrl, Peter The stability of the exponential equation. (English) Zbl 0846.39013 Proc. Am. Math. Soc. 124, No. 3, 779-787 (1996). Reviewer: Pl.Kannappan (Waterloo / Ontario) MSC: 39B72 39B52 PDFBibTeX XMLCite \textit{R. Ger} and \textit{P. Semrl}, Proc. Am. Math. Soc. 124, No. 3, 779--787 (1996; Zbl 0846.39013) Full Text: DOI
Alsina, Claudi; García-Roig, Jaime L.; Ger, Roman How to keep the quadrilateral inscribed. (English) Zbl 0851.39009 Abh. Math. Semin. Univ. Hamb. 65, 123-133 (1995). Reviewer: N.Ghircoiaşiu (Cluj-Napoca) MSC: 39B52 PDFBibTeX XMLCite \textit{C. Alsina} et al., Abh. Math. Semin. Univ. Hamb. 65, 123--133 (1995; Zbl 0851.39009) Full Text: DOI
Ger, Roman Mazur’s criterion for continuity of convex functionals. (English) Zbl 0841.39005 Bull. Pol. Acad. Sci., Math. 43, No. 3, 263-268 (1995). Reviewer: G.L.Forti (Milano) MSC: 39B52 26B25 46A30 PDFBibTeX XMLCite \textit{R. Ger}, Bull. Pol. Acad. Sci., Math. 43, No. 3, 263--268 (1995; Zbl 0841.39005)
Ger, Roman; Sikorska, Justyna Stability of the orthogonal additivity. (English) Zbl 0833.39007 Bull. Pol. Acad. Sci., Math. 43, No. 2, 143-151 (1995). Reviewer: Th.M.Rassias (Athens) MSC: 39B72 39B52 46B20 PDFBibTeX XMLCite \textit{R. Ger} and \textit{J. Sikorska}, Bull. Pol. Acad. Sci., Math. 43, No. 2, 143--151 (1995; Zbl 0833.39007)
Ger, Roman Stability aspects of delta-convexity. (English) Zbl 0845.39012 Rassias, Themistocles M. (ed.) et al., Stability of mappings of Hyers-Ulam type. Palm Harbor, FL: Hadronic Press. 99-109 (1994). MSC: 39B72 39B52 PDFBibTeX XMLCite \textit{R. Ger}, in: Stability of mappings of Hyers-Ulam type. Palm Harbor, FL: Hadronic Press. 99--109 (1994; Zbl 0845.39012)
Ger, Roman On extension of polynomial functions. (English) Zbl 0829.39006 Result. Math. 26, No. 3-4, 281-289 (1994). Reviewer: C.Alsina (Barcelona) MSC: 39B52 39A70 47B39 46S10 PDFBibTeX XMLCite \textit{R. Ger}, Result. Math. 26, No. 3--4, 281--289 (1994; Zbl 0829.39006) Full Text: DOI
Ger, Roman On a factorization of mappings with a prescribed behaviour of the Cauchy difference. (English) Zbl 0820.39014 Pr. Nauk. Uniw. Śląsk. Katowicach 1444, Ann. Math. Silesianae 8, 141-155 (1994). Reviewer: G.L.Forti (Milano) MSC: 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Pr. Nauk. Uniw. Śląsk. Katowicach, Ann. Math. Silesianae 1444(8), 141--155 (1994; Zbl 0820.39014)
Ger, Roman (ed.) Polish-Austrian seminar on functional equations and iteration theory, held October 26-31, 1994 in Cieszyn, Poland. (English) Zbl 0810.00018 Pr. Nauk. Uniw. Śląsk. Katowicach 1444, Ann. Math. Silesianae 8, 240 p. (1994). MSC: 00B25 39-06 PDFBibTeX XML
Ger, Roman Stability of polynomial mappings controlled by \(n\)-convex functionals. (English) Zbl 0882.39011 Agarwal, R. P. (ed.), Inequalities and applications. Dedicated to Wolfgang Walter’s 66th birthday with a tribute by R. M. Redheffer. Singapore: World Scientific. World Sci. Ser. Appl. Anal. 3, 255-268 (1994). MSC: 39B72 39A70 26A51 39B22 PDFBibTeX XMLCite \textit{R. Ger}, World Sci. Ser. Appl. Anal. 3, 255--268 (1994; Zbl 0882.39011)
Ger, Roman On a characterization of strictly convex spaces. (English) Zbl 0843.46010 Atti Accad. Sci. Torino, Cl. Sci. Fis. Mat. Nat. 127, No. 3-4, 131-138 (1993). MSC: 46B20 39B05 PDFBibTeX XMLCite \textit{R. Ger}, Atti Accad. Sci. Torino, Cl. Sci. Fis. Mat. Nat. 127, No. 3--4, 131--138 (1993; Zbl 0843.46010)
Ger, Roman Joint continuity of Christensen measurable multiadditive maps. (English) Zbl 0841.28013 Tatra Mt. Math. Publ. 2, 93-103 (1993). Reviewer: Z.Lipecki (Wrocław) MSC: 28C10 22A10 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Tatra Mt. Math. Publ. 2, 93--103 (1993; Zbl 0841.28013)
Ger, Roman Superstability is not natural. (English) Zbl 0964.39503 Rocz. Nauk.-Dydakt., Pr. Mat. 13, 109-123 (1993). MSC: 39B22 20M99 22A25 PDFBibTeX XMLCite \textit{R. Ger}, Rocz. Nauk.-Dydakt., Pr. Mat. 13, 109--123 (1993; Zbl 0964.39503)
Ger, Roman The singular case in the stability behaviour of linear mappings. (English) Zbl 0796.39012 Grazer Math. Ber. 316, 59-70 (1992). Reviewer: D.H.Hyers MSC: 39B52 39B72 PDFBibTeX XMLCite \textit{R. Ger}, Grazer Math. Ber. 316, 59--70 (1992; Zbl 0796.39012)
Ger, Roman M.Kuczma’s papers on functional equations in several variables. (English) Zbl 0783.39005 Grazer Math. Ber. 316, 17-28 (1992). MSC: 39B22 39-03 01A70 PDFBibTeX XMLCite \textit{R. Ger}, Grazer Math. Ber. 316, 17--28 (1992; Zbl 0783.39005) Full Text: EuDML
Ger, J.; Ger, R. On some aspects of Jensen-Menger convexity. (English) Zbl 0806.46011 Stochastica 13, No. 1, 43-60 (1992). MSC: 46A55 46A30 46N10 PDFBibTeX XMLCite \textit{J. Ger} and \textit{R. Ger}, Stochastica 13, No. 1, 43--60 (1992; Zbl 0806.46011) Full Text: EuDML
Ger, Roman On functional inequalities stemming from stability questions. (English) Zbl 0770.39007 General inequalities 6, Proc. 6th Int. Conf., Oberwolfach/Ger. 1990, ISNM 103, 227-240 (1992). Reviewer: A.Smajdor (Katowice) MSC: 39B72 PDFBibTeX XMLCite \textit{R. Ger}, in: General inequalities 6. 6th international conference on general inequalities, Oberwolfach, Germany, Dec. 9-15, 1990. Basel etc.: Birkhäuser Verlag. 227--240 (1992; Zbl 0770.39007)
Ger, Roman Stability of addition formulae for trigonometric mappings. (English) Zbl 0741.39010 Zesz. Nauk. Politech. Śląsk. 1070, Mat.-Fiz. 64, 75-84 (1991). Reviewer: H.L.Vasudeva (Chandigarh) MSC: 39B32 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Zesz. Nauk. Politech. Śląsk. Mat.-Fiz. 1070(64), 75--84 (1991; Zbl 0741.39010)
Kuczma, Marek; Choczewski, Bogdan; Ger, Roman Iterative functional equations. (English) Zbl 0703.39005 Encyclopedia of Mathematics and Its Applications, 32. Cambridge etc.: Cambridge University Press. xiv, 552 p. £55.00/hbk; $ 99.50/hbk (1990). Reviewer: W.Jarczyk MSC: 39B12 39-02 39B22 39B52 39B72 PDFBibTeX XMLCite \textit{M. Kuczma} et al., Iterative functional equations. Cambridge etc.: Cambridge University Press (1990; Zbl 0703.39005)
Ger, R.; Kominek, Z. Boundedness and continuity of additive and convex functionals. (English) Zbl 0702.46004 Aequationes Math. 37, No. 2-3, 252-258 (1989). Reviewer: J.Smítal MSC: 46A55 39B52 PDFBibTeX XMLCite \textit{R. Ger} and \textit{Z. Kominek}, Aequationes Math. 37, No. 2--3, 252--258 (1989; Zbl 0702.46004) Full Text: DOI EuDML
Ger, R. Some remarks on quadratic functionals. (English) Zbl 0674.39013 Glas. Mat., III. Ser. 23(43), No. 2, 315-330 (1988). Reviewer: J.Aczél MSC: 39B52 46C99 PDFBibTeX XMLCite \textit{R. Ger}, Glas. Mat., III. Ser. 23(43), No. 2, 315--330 (1988; Zbl 0674.39013)
Ger, Roman Errata for the paper: Almost approximately convex functions. (English) Zbl 0659.39005 Math. Slovaca 38, No. 4, 423 (1988). Reviewer: J.Aczél MSC: 39B72 26A51 PDFBibTeX XMLCite \textit{R. Ger}, Math. Slovaca 38, No. 4, 423 (1988; Zbl 0659.39005) Full Text: EuDML
Alsina, Claudi; Ger, Roman On associative copulas uniformly close. (English) Zbl 0655.39006 Int. J. Math. Math. Sci. 11, No. 3, 439-448 (1988). Reviewer: I.Corovei MSC: 39B72 PDFBibTeX XMLCite \textit{C. Alsina} and \textit{R. Ger}, Int. J. Math. Math. Sci. 11, No. 3, 439--448 (1988; Zbl 0655.39006) Full Text: DOI EuDML
Ger, Roman Christensen measurability and functional equations. (English) Zbl 0654.39005 Ber. Math.-Stat. Sekt. Forschungsges. Joanneum-Graz 285-296, 289/1-289/17 (1988). Reviewer: Pl.Kannappan MSC: 39B99 39B52 PDFBibTeX XML
Ger, Roman Almost approximately convex functions. (English) Zbl 0641.39006 Math. Slovaca 38, No. 1, 61-78 (1988). Reviewer: J.Aczél MSC: 39B72 16L30 28C10 46A03 03E15 PDFBibTeX XMLCite \textit{R. Ger}, Math. Slovaca 38, No. 1, 61--78 (1988; Zbl 0641.39006) Full Text: EuDML
Ger, Roman Convex transformations with Banach lattice range. (English) Zbl 0675.46012 Stochastica 11, No. 1, 13-23 (1987). Reviewer: C.B.Huijsmans MSC: 46B42 46A40 26A51 PDFBibTeX XMLCite \textit{R. Ger}, Stochastica 11, No. 1, 13--23 (1987; Zbl 0675.46012) Full Text: EuDML
Gajda, Zbigniew; Ger, Roman Subadditive multifunctions and Hyers-Ulam stability. (English) Zbl 0639.39014 General inequalities 5, 5th Int. Conf., Oberwolfach/FRG 1986, ISNM 80, 281-291 (1987). Reviewer: A.Smajdor MSC: 39B72 54C60 54C65 PDFBibTeX XML
Ger, R.; Kominek, Z.; Sablik, M. Generalized Smital’s lemma and a theorem of Steinhaus. (English) Zbl 0587.28008 Rad. Mat. 1, No. 1, 101-119 (1985). MSC: 28C15 28A12 PDFBibTeX XMLCite \textit{R. Ger} et al., Rad. Mat. 1, No. 1, 101--119 (1985; Zbl 0587.28008)
Ger, Roman A consistency equation for three geometries. (English) Zbl 0577.51016 Aequationes Math. 29, 50-55 (1985). Reviewer: O.Bottema MSC: 51M10 51M05 39B99 PDFBibTeX XMLCite \textit{R. Ger}, Aequationes Math. 29, 50--55 (1985; Zbl 0577.51016) Full Text: DOI EuDML
Alsina, C.; Ger, R. Associative operations close to a given one. (English) Zbl 0575.39006 C. R. Math. Acad. Sci., Soc. R. Can. 7, 207-210 (1985). Reviewer: B.Choczewski MSC: 39B99 PDFBibTeX XMLCite \textit{C. Alsina} and \textit{R. Ger}, C. R. Math. Acad. Sci., Soc. R. Can. 7, 207--210 (1985; Zbl 0575.39006)
Ger, Roman Almost approximately additive mappings. (English) Zbl 0519.39009 General inequalities 3, 3rd int. Conf., Oberwolfach 1981, ISNM 64, 263-276 (1983). MSC: 39B72 39B52 PDFBibTeX XML
Ger, Roman Homogeneity sets for Jensen-convex functions. (English) Zbl 0456.26007 General inequalities 2, Proc. 2nd int. Conf., Oberwolfach 1978, ISNM Vol. 47, 193-201 (1980). MSC: 26B25 26A51 46A55 15A03 PDFBibTeX XML
Ger, Roman Almost additive functions on semigroups and a functional equation. (English) Zbl 0444.39004 Publ. Math. Debr. 26, 219-228 (1979). MSC: 39B52 39B99 PDFBibTeX XMLCite \textit{R. Ger}, Publ. Math. Debr. 26, 219--228 (1979; Zbl 0444.39004)
Ger, Roman Note on almost additive functions. (English) Zbl 0441.39008 Aequationes Math. 17, 73-76 (1978). MSC: 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Aequationes Math. 17, 73--76 (1978; Zbl 0441.39008) Full Text: DOI EuDML
Ger, Roman Almost subadditive functions. (English) Zbl 0389.26005 Allgem. Ungleichg. 1, Tag. Oberwolfach 1976, ISNM 41, 159-167 (1978). MSC: 26A48 26A51 PDFBibTeX XML
Dhombres, J. G.; Ger, R. Conditional Cauchy equations. (English) Zbl 0384.39004 Glas. Mat., III. Ser. 13(33), 39-62 (1978). MSC: 39B52 39B99 20K30 PDFBibTeX XMLCite \textit{J. G. Dhombres} and \textit{R. Ger}, Glas. Mat., III. Ser. 13(33), 39--62 (1978; Zbl 0384.39004)
Ger, Roman On some functional equations with a restricted domain. II. (English) Zbl 0382.39005 Fundam. Math. 98, 249-272 (1978). MSC: 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Fundam. Math. 98, 249--272 (1978; Zbl 0382.39005) Full Text: DOI EuDML OA License
Ger, Roman Functional equations with a restricted domain. (English) Zbl 0407.39003 Rend. Sem. Mat. Fis. Milano 47, 175-184 (1977). MSC: 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Rend. Semin. Mat. Fis. Milano 47, 175--184 (1977; Zbl 0407.39003) Full Text: DOI
Ger, Roman On an alternative functional equation. (English) Zbl 0361.39005 Aequationes Math. 15, 145-162 (1977). MSC: 39B52 39B05 PDFBibTeX XMLCite \textit{R. Ger}, Aequationes Math. 15, 145--162 (1977; Zbl 0361.39005) Full Text: DOI EuDML
Ger, Roman On a method of solving of conditional Cauchy equations. (English) Zbl 0348.39003 Publ. Fac. Electrotech. Univ. Belgrade, Ser. Math. Phys. 544-576 (1976), 159-165 (1977). MSC: 39B05 PDFBibTeX XMLCite \textit{R. Ger}, Publ. Fac. Électrotech. Univ. Belgrade, Sér. Math. Phys. 544--576, 159--165 (1977; Zbl 0348.39003)
Baron, Karol; Ger, Roman Lyapunov stability of continuous solutions of some functional equations. (English) Zbl 0366.39003 An. Stiint. Univ. Al. I. Cuza Iasi, n. Ser., Sect. Ia 22, 165-172 (1976). MSC: 39B05 65Q05 PDFBibTeX XMLCite \textit{K. Baron} and \textit{R. Ger}, An. Științ. Univ. Al. I. Cuza Iași, N. Ser., Secț. Ia 22, 165--172 (1976; Zbl 0366.39003)
Ger, Roman; Smajdor, Andrzej p-convex iteration groups. (English) Zbl 0357.26005 Fundam. Math. 91, 29-38 (1976). MSC: 26A51 26A18 39B05 PDFBibTeX XMLCite \textit{R. Ger} and \textit{A. Smajdor}, Fundam. Math. 91, 29--38 (1976; Zbl 0357.26005) Full Text: DOI EuDML
Ger, R. On some functional equations with a restricted domain. (English) Zbl 0345.39008 Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 24, 429-432 (1976). MSC: 39B52 39B05 39B99 PDFBibTeX XMLCite \textit{R. Ger}, Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 24, 429--432 (1976; Zbl 0345.39008)
Baron, Karol; Ger, Roman An integral version of some theorems occuring in the theory of functional equations. (English) Zbl 0423.39003 Math., Rev. Anal. Numér. Théor. Approximation, Math. 17(40), 5-10 (1975). MSC: 39B12 39B52 PDFBibTeX XMLCite \textit{K. Baron} and \textit{R. Ger}, Math. Rev. Anal. Numér. Théor. Approximation, Math. 17(40), 5--10 (1975; Zbl 0423.39003)
Ger, Roman On some functional equations with a restricted domain. (English) Zbl 0322.39017 Fundam. Math. 89, 131-149 (1975). MSC: 39B52 PDFBibTeX XMLCite \textit{R. Ger}, Fundam. Math. 89, 131--149 (1975; Zbl 0322.39017) Full Text: DOI EuDML
Baron, K.; Ger, R.; Matkowski, J. Analytic solutions of a system of functional equations. (English) Zbl 0322.39016 Publ. Math. Debr. 22, 189-194 (1975). MSC: 39B99 PDFBibTeX XMLCite \textit{K. Baron} et al., Publ. Math. Debr. 22, 189--194 (1975; Zbl 0322.39016)