@article{DE_1975_11_1_a4,
     author = {V. P. Didenko},
     title = {Boundary value problems for a three-dimensional equation of mixed type},
     journal = {Differencialʹnye uravneni\^a},
     pages = {33--37},
     year = {1975},
     volume = {11},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1975_11_1_a4/}
}