TY - JOUR AU - Hata, Kazuya AU - Liu, Jiaquan AU - Wang, Zhi-Qiang PY - 2013/04/22 Y2 - 2024/03/28 TI - Note on periodic solutions of relativistic pendulum type systems JF - Topological Methods in Nonlinear Analysis JA - TMNA VL - 42 IS - 2 SE - DO - UR - https://apcz.umk.pl/TMNA/article/view/TMNA.2013.043 SP - 417 - 425 AB - We establish multiplicity results of periodic solutions forrelativistic pendulum type systems of ordinary differentialequations. We provide a different approach to the problems andanswer some questions raised in \cite{6}, \cite{7} by Brezis andMawhin recently. ER -