@article{DE_1976_12_11_a0,
     author = {N. V. Azbelev},
     title = {Nonlinear functional-differential equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1923--1932},
     year = {1976},
     volume = {12},
     number = {11},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1976_12_11_a0/}
}