@article{MZ_1957__68_169700,
     author = {Ky Fan},
     title = {Existence {Theorems} and {Extreme} {Solutions} for {Inequalities} {Concerning} {Convex} {Functions} or {Linear} {Transformations.}},
     journal = {Mathematische Zeitschrift},
     pages = {205--216},
     publisher = {mathdoc},
     volume = {68},
     year = {1957},
     zbl = {0078.10204},
     url = {http://geodesic.mathdoc.fr/item/MZ_1957__68_169700/}
}