@article{FAA_1972_6_3_a10,
     author = {K. \'E. Vega},
     title = {On the completeness of a subsystem of eigenfunctions of one class of boundary value problems},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {65--67},
     publisher = {mathdoc},
     volume = {6},
     number = {3},
     year = {1972},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1972_6_3_a10/}
}