@article{DE_1973_9_10_a15,
     author = {A. F. Filippov},
     title = {Smoothness of generalized solutions near the vertex of a polyhedral angle},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1889--1903},
     publisher = {mathdoc},
     volume = {9},
     number = {10},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1973_9_10_a15/}
}