@article{DE_1976_12_8_a13,
     author = {V. S. Kostin},
     title = {The smoothness of the solutions of certain equations of parabolic {type.~I}},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1495--1506},
     year = {1976},
     volume = {12},
     number = {8},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1976_12_8_a13/}
}