@article{DAN_1989_304_5_a2,
     author = {V. I. Vasyunin},
     title = {Multiplicity of a spectrum of contractions with finite defect},
     journal = {Doklady Akademii Nauk},
     pages = {1041--1043},
     publisher = {mathdoc},
     volume = {304},
     number = {5},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1989_304_5_a2/}
}