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@article{DE_1971_7_6_a3, author = {S. T. Zavalishchin}, title = {On the question of the general form of a linear equation. {I,} {II}}, journal = {Differencialʹnye uravneni\^a}, pages = {981--989}, publisher = {mathdoc}, volume = {7}, number = {6}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1971_7_6_a3/} }
S. T. Zavalishchin. On the question of the general form of a linear equation. I, II. Differencialʹnye uravneniâ, Tome 7 (1971) no. 6, pp. 981-989. http://geodesic.mathdoc.fr/item/DE_1971_7_6_a3/