@article{DE_1975_11_8_a14,
     author = {A. Azamov},
     title = {The measure of nonregularity of quasitriangular systems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1497--1500},
     publisher = {mathdoc},
     volume = {11},
     number = {8},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1975_11_8_a14/}
}