中国科学院数学与系统科学研究院期刊网
AMS
A Variational Principle and Best Proximity Points
Milen IVANOV, Boyan ZLATANOV, Nadia ZLATEVA
Acta Mathematica Sinica . 2015, (8): 1315 -1326 .  DOI: 10.1007/s10114-015-4538-4