@article{DE_1984_20_11_a17,
     author = {S. M. Shugrin},
     title = {A system of inequalities connected with elliptic and parabolic operators},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1975--1985},
     publisher = {mathdoc},
     volume = {20},
     number = {11},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1984_20_11_a17/}
}