@article{DE_1973_9_8_a14,
     author = {L. N. Lyapin},
     title = {Set-valued mappings in the theory of integral equations with a discontinuous operator},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1511--1519},
     publisher = {mathdoc},
     volume = {9},
     number = {8},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1973_9_8_a14/}
}