@article{DE_1976_12_4_a22,
     author = {H. M. Nadzafov},
     title = {On the {Tricomi} problem for a second order linear equation of mixed type},
     journal = {Differencialʹnye uravneni\^a},
     pages = {763--765},
     publisher = {mathdoc},
     volume = {12},
     number = {4},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1976_12_4_a22/}
}