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@article{DE_1973_9_1_a3, author = {A. A. Dezin}, title = {Natural differential operators and the separation of variables}, journal = {Differencialʹnye uravneni\^a}, pages = {25--31}, publisher = {mathdoc}, volume = {9}, number = {1}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1973_9_1_a3/} }
A. A. Dezin. Natural differential operators and the separation of variables. Differencialʹnye uravneniâ, Tome 9 (1973) no. 1, pp. 25-31. http://geodesic.mathdoc.fr/item/DE_1973_9_1_a3/