Szulkin, Andrzej An index theory and existence of multiple brake orbits for star-shaped Hamiltonian systems. (English) Zbl 0642.58030 Math. Ann. 283, No. 3, 241-255 (1989). Reviewer: A.Szulkin MSC: 37J99 37G99 PDFBibTeX XMLCite \textit{A. Szulkin}, Math. Ann. 283, No. 3, 241--255 (1989; Zbl 0642.58030) Full Text: DOI EuDML
Szulkin, Andrzej Morse theory and existence of periodic solutions of convex Hamiltonian systems. (English) Zbl 0669.58004 Bull. Soc. Math. Fr. 116, No. 2, 171-197 (1988). Reviewer: M.Tucsnak MSC: 58E05 34C25 PDFBibTeX XMLCite \textit{A. Szulkin}, Bull. Soc. Math. Fr. 116, No. 2, 171--197 (1988; Zbl 0669.58004) Full Text: DOI Numdam EuDML
Szulkin, Andrzej On the number of solutions of some semilinear elliptic boundary value problems. (English) Zbl 0537.35034 Nonlinear Anal., Theory Methods Appl. 6, 95-116 (1982). Reviewer: G.Buttazzo MSC: 35J65 35J25 35J40 35B32 PDFBibTeX XMLCite \textit{A. Szulkin}, Nonlinear Anal., Theory Methods Appl. 6, 95--116 (1982; Zbl 0537.35034) Full Text: DOI