@article{DE_1995_31_10_a4,
     author = {A. Ya. Dubovitskii and V. A. Dubovitskii},
     title = {A criterion for the existence of a meaningful maximum principle in a problem with phase constraints},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1634--1640},
     publisher = {mathdoc},
     volume = {31},
     number = {10},
     year = {1995},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1995_31_10_a4/}
}