王少敏,熊明,茶国智.一类非自治二阶哈密顿系统周期解的存在性[J].重庆工商大学学报（自然科学版）,2008,(1):
WANG Shao-min, XIONG Ming, CHA Guo-zhi. Existence of periodic solutions for a class of non-autonomous second order Hamiltonian Systems[J]. Journal of Chongqing Technology and Business University(Natural Science Edition）,2008,(1):