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@article{DE_1973_9_1_a5, author = {V. I. Evsin}, title = {The {Holmgren} problem for a certain equation with singular coefficients}, journal = {Differencialʹnye uravneni\^a}, pages = {41--48}, publisher = {mathdoc}, volume = {9}, number = {1}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1973_9_1_a5/} }
V. I. Evsin. The Holmgren problem for a certain equation with singular coefficients. Differencialʹnye uravneniâ, Tome 9 (1973) no. 1, pp. 41-48. http://geodesic.mathdoc.fr/item/DE_1973_9_1_a5/