@article{10_4153_CJM_1992_046_9,
     author = {Ding, Xie Ping and Tan, Kok-Keong},
     title = {A {Set-Valued} {Generalization} of {Fan's} {Best} {Approximation} {Theorem}},
     journal = {Canadian journal of mathematics},
     pages = {784--796},
     year = {1992},
     volume = {44},
     number = {4},
     doi = {10.4153/CJM-1992-046-9},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1992-046-9/}
}