二阶非线性常微分方程组周期边值问题的正解

刘健,封汉颍

Positive solutions of periodic BVP for systems of nonlinear second-order ordinary differential equations

LIU Jian,FENG Hanying

河北大学学报(自然科学版) . 2014, (5): 455 -459 . DOI: 10.3969/j.issn.1000-1565.2014.05.002