@article{ZVMMF_1986_26_10_a12,
     author = {A. V. Gulin and S. I. Kovalev},
     title = {On the spectrum of a certain difference scheme on irregular networks},
     journal = {\v{Z}urnal vy\v{c}islitelʹnoj matematiki i matemati\v{c}eskoj fiziki},
     pages = {1578--1583},
     publisher = {mathdoc},
     volume = {26},
     number = {10},
     year = {1986},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZVMMF_1986_26_10_a12/}
}