@article{DE_1983_19_11_a31,
     author = {R. K. Ragimkhanov},
     title = {On the question of the existence of upper and lower solutions of the {Hammerstein} integral inclusion},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2011--2013},
     publisher = {mathdoc},
     volume = {19},
     number = {11},
     year = {1983},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1983_19_11_a31/}
}