@article{DE_1972_8_5_a1,
     author = {Yu. P. Boglaev},
     title = {On the theory of singularly perturbed problems with branch points for degenerate equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {762--766},
     publisher = {mathdoc},
     volume = {8},
     number = {5},
     year = {1972},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1972_8_5_a1/}
}