@article{DE_1971_7_11_a13,
     author = {I. I. Golichev},
     title = {The existence of a point of regularity and the spectrum of a second order nonselfadjoint differential operator},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2051--2057},
     publisher = {mathdoc},
     volume = {7},
     number = {11},
     year = {1971},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1971_7_11_a13/}
}