@article{DE_1970_6_9_a18,
     author = {A. V. Kostin},
     title = {The real singular points of the solutions of second order nonlinear differential equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1713--1715},
     publisher = {mathdoc},
     volume = {6},
     number = {9},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1970_6_9_a18/}
}