@article{FAA_1974_8_2_a19,
     author = {I. F. Kushnirchuk and N. I. Nagnibida and K. M. Fishman},
     title = {Equivalence of differential operators with a regular singular point},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {83--84},
     publisher = {mathdoc},
     volume = {8},
     number = {2},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1974_8_2_a19/}
}