@article{DE_1996_32_8_a4,
     author = {B. S. Kalitin},
     title = {Pseudoprolongation},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1043--1050},
     publisher = {mathdoc},
     volume = {32},
     number = {8},
     year = {1996},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1996_32_8_a4/}
}