中国科学院数学与系统科学研究院期刊网
AMS
A Generalized Vector-valued Variational Principle in Frechet Spaces
Jing Hui QIU, Xin Qing YANG
Acta Mathematica Sinica . 2010, (11): 2145 -2156 .  DOI: 10.1007/s10114-010-8524-6