@article{DE_1968_4_11_a17,
     author = {O. N. Litvin and V. L. Rvachev and V. K. Yarmoluk},
     title = {The solution of a certain class of boundary value problems with mixed boundary conditions for regions of composite form},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2089--2093},
     publisher = {mathdoc},
     volume = {4},
     number = {11},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1968_4_11_a17/}
}