中国科学院数学与系统科学研究院期刊网
AMS
Sequentially Lower Complete Spaces and Ekeland's Variational Principle
Fei HE, Jing-Hui QIU
Acta Mathematica Sinica . 2015, (8): 1289 -1302 .  DOI: 10.1007/s10114-015-4541-9