Komorowski, Jacek On an estimate from below for the first positive eigenvalue of \(\Delta\). (English) Zbl 0416.58026 Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 999-1006 (1977). MSC: 58J50 53C20 PDFBibTeX XMLCite \textit{J. Komorowski}, Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 999--1006 (1977; Zbl 0416.58026)
Kijowski, Jerzy; Smolski, Adam Darboux’s theorem and the linearization of ordinary differential equations. (English) Zbl 0378.53014 Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 671-673 (1977). MSC: 53C15 37-XX PDFBibTeX XMLCite \textit{J. Kijowski} and \textit{A. Smolski}, Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 671--673 (1977; Zbl 0378.53014)
de la Harpe, Pierre On noncompact Lie groups acting transitively on spheres. (English) Zbl 0368.57014 Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 501-506 (1977). MSC: 57S25 53C05 57S20 PDFBibTeX XMLCite \textit{P. de la Harpe}, Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 501--506 (1977; Zbl 0368.57014)
Derdzinski, Andrzej On the existence of essentially conformally symmetric non-Ricci-recurrent manifolds. (English) Zbl 0362.53039 Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 539-541 (1977). MSC: 53C25 53B20 PDFBibTeX XMLCite \textit{A. Derdzinski}, Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 539--541 (1977; Zbl 0362.53039)
Tafel, Jacek Cosmological models with a spinor field. (English) Zbl 0361.53060 Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 593-596 (1977). MSC: 53C99 53B99 53C27 PDFBibTeX XMLCite \textit{J. Tafel}, Bull. Acad. Pol. Sci., Sér. Sci. Math. Astron. Phys. 25, 593--596 (1977; Zbl 0361.53060)