@article{MZM_1999_66_6_a2,
     author = {G. E. Ivanov},
     title = {Continuity of optimal controls in differential games, and some properties of weakly and strongly convex functions},
     journal = {Matemati\v{c}eskie zametki},
     pages = {816--839},
     publisher = {mathdoc},
     volume = {66},
     number = {6},
     year = {1999},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1999_66_6_a2/}
}