@article{DE_1977_13_11_a10,
     author = {A. V. Bitsadze},
     title = {On the theory of a class of nonlinear partial differential equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1993--2008},
     publisher = {mathdoc},
     volume = {13},
     number = {11},
     year = {1977},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1977_13_11_a10/}
}