@article{ZVMMF_1981_21_6_a11,
     author = {Yu. V. Shestopalov},
     title = {On the spectrum of a family of non-self-adjoint boundary value problems for systems of {Helmholtz} equations},
     journal = {\v{Z}urnal vy\v{c}islitelʹnoj matematiki i matemati\v{c}eskoj fiziki},
     pages = {1459--1470},
     publisher = {mathdoc},
     volume = {21},
     number = {6},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZVMMF_1981_21_6_a11/}
}