Adam, M.; Czerwik, S. Quadratic operators and quadratic functional equation. (English) Zbl 1248.39020 Pardalos, Panos M. (ed.) et al., Nonlinear analysis. Stability, approximation, and inequalities. In honor of Themistocles M. Rassias on the occasion of his 60th birthday. New York, NY: Springer (ISBN 978-1-4614-3497-9/hbk; 978-1-4614-3498-6/ebook). Springer Optimization and Its Applications 68, 13-37 (2012). MSC: 39B82 39B52 39A70 47B39 PDFBibTeX XMLCite \textit{M. Adam} and \textit{S. Czerwik}, Springer Optim. Appl. 68, 13--37 (2012; Zbl 1248.39020) Full Text: DOI
Czerwik, Stefan On stability of the equation of homogeneous functions on topological spaces. (English) Zbl 1248.39027 Rassias, Themistocles M. (ed.) et al., Functional equations in mathematical analysis. Dedicated to the memory of Stanisław Marcin Ulam on the occasion of the 100th anniversary of his birth. Berlin: Springer (ISBN 978-1-4614-0054-7/hbk; 978-1-4614-0055-4/ebook). Springer Optimization and Its Applications 52, 87-96 (2011). MSC: 39B82 39B52 PDFBibTeX XMLCite \textit{S. Czerwik}, Springer Optim. Appl. 52, 87--96 (2011; Zbl 1248.39027) Full Text: DOI
Czerwik, Stefan; Król, Krzysztof Ulam-Hyers-Rassias stability of functional equations. (English) Zbl 1382.39036 Nonlinear Funct. Anal. Appl. 14, No. 5, 39b82 39b62 (2009). MSC: 39B82 39B62 PDFBibTeX XMLCite \textit{S. Czerwik} and \textit{K. Król}, Nonlinear Funct. Anal. Appl. 14, No. 5, 39b82 39b62 (2009; Zbl 1382.39036)
Czerwik, Stefan; Król, Krzysztof Ulam stability of functional equations. (English) Zbl 1175.39017 Aust. J. Math. Anal. Appl. 6, No. 1, Article 6, 15 p. (2009). MSC: 39B82 PDFBibTeX XMLCite \textit{S. Czerwik} and \textit{K. Król}, Aust. J. Math. Anal. Appl. 6, No. 1, Article 6, 15 p. (2009; Zbl 1175.39017) Full Text: Link
Czerwik, Stefan; Przybyła, Maciej A general Baker superstability criterion for the D’Alembert functional equation. (English) Zbl 1135.39012 Randrianantoanina, Beata (ed.) et al., Banach spaces and their applications in analysis. Proceedings of the international conference, Miami University, Oxford, OH, USA, May 22–27, 2006. In honor of Nigel Kalton’s 60th birthday. Berlin: Walter de Gruyter (ISBN 978-3-11-019449-4/hbk). 303-306 (2007). MSC: 39B82 39B52 PDFBibTeX XMLCite \textit{S. Czerwik} and \textit{M. Przybyła}, in: Banach spaces and their applications in analysis. Proceedings of the international conference, Miami University, Oxford, OH, USA, May 22--27, 2006. In honor of Nigel Kalton's 60th birthday. Berlin: Walter de Gruyter. 303--306 (2007; Zbl 1135.39012)
Adam, M.; Czerwik, S. On the stability of the quadratic functional equation in topological spaces. (English) Zbl 1130.39021 Banach J. Math. Anal. 1, No. 2, 245-251 (2007). Reviewer: Jacek Chmielinski (Kraków) MSC: 39B82 39B52 PDFBibTeX XMLCite \textit{M. Adam} and \textit{S. Czerwik}, Banach J. Math. Anal. 1, No. 2, 245--251 (2007; Zbl 1130.39021) Full Text: DOI EuDML EMIS
Czerwik, S. Some results on the stability of the homogeneous functions. (English) Zbl 1074.39026 Bull. Korean Math. Soc. 42, No. 1, 29-37 (2005). Reviewer: Soon-Mo Jung (Chochiwon) MSC: 39B82 39B52 PDFBibTeX XMLCite \textit{S. Czerwik}, Bull. Korean Math. Soc. 42, No. 1, 29--37 (2005; Zbl 1074.39026) Full Text: DOI
Czerwik, S.; Dłutek, K. Stability of the quadratic functional equation in Lipschitz spaces. (English) Zbl 1052.39030 J. Math. Anal. Appl. 293, No. 1, 79-88 (2004). Reviewer: Szymon Wąsowicz (Bielsko-Biała) MSC: 39B82 39B52 PDFBibTeX XMLCite \textit{S. Czerwik} and \textit{K. Dłutek}, J. Math. Anal. Appl. 293, No. 1, 79--88 (2004; Zbl 1052.39030) Full Text: DOI
Czerwik, Stefan; Dłutek, Krzysztof Superstability of the equation of quadratic functionals in \(L^p\)-spaces. (English) Zbl 1062.39030 Aequationes Math. 63, No. 3, 210-219 (2002). MSC: 39B82 46E30 39B52 PDFBibTeX XMLCite \textit{S. Czerwik} and \textit{K. Dłutek}, Aequationes Math. 63, No. 3, 210--219 (2002; Zbl 1062.39030) Full Text: DOI