@article{FAA_1968_2_2_a10,
     author = {G. M. Vainikko and Yu. B. Umanskii},
     title = {Regular operators},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {87--88},
     publisher = {mathdoc},
     volume = {2},
     number = {2},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1968_2_2_a10/}
}