@article{DE_1973_9_7_a8,
     author = {T. Yu. Petrenko},
     title = {The properties of the {Bellman} function},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1244--1255},
     year = {1973},
     volume = {9},
     number = {7},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1973_9_7_a8/}
}