@article{DE_1988_24_4_a32, author = {T. V. Chekmarev}, title = {A nonlocal problem for a system of equations of {Helmholtz} type}, journal = {Differencialʹnye uravneni\^a}, pages = {724--726}, publisher = {mathdoc}, volume = {24}, number = {4}, year = {1988}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1988_24_4_a32/} }