@article{DE_1993_29_5_a1,
     author = {S. A. Brykalov},
     title = {Solvability of problems with monotone boundary conditions},
     journal = {Differencialʹnye uravneni\^a},
     pages = {744--750},
     publisher = {mathdoc},
     volume = {29},
     number = {5},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1993_29_5_a1/}
}