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@article{DE_1986_22_5_a25, author = {P. G. Lasy}, title = {A linear completely integrable {Pfaffian} equation having a given characteristic set}, journal = {Differencialʹnye uravneni\^a}, pages = {896--897}, publisher = {mathdoc}, volume = {22}, number = {5}, year = {1986}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1986_22_5_a25/} }
P. G. Lasy. A linear completely integrable Pfaffian equation having a given characteristic set. Differencialʹnye uravneniâ, Tome 22 (1986) no. 5, pp. 896-897. http://geodesic.mathdoc.fr/item/DE_1986_22_5_a25/