@article{FPM_2006_12_5_a4,
     author = {Kh. K. Ishkin},
     title = {On localization of the spectrum of the problem with complex weight},
     journal = {Fundamentalʹna\^a i prikladna\^a matematika},
     pages = {49--64},
     publisher = {mathdoc},
     volume = {12},
     number = {5},
     year = {2006},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FPM_2006_12_5_a4/}
}