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@article{DE_1989_25_3_a13, author = {M. Utepbergenov}, title = {A method for studying regular singularities of partial differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {499--505}, publisher = {mathdoc}, volume = {25}, number = {3}, year = {1989}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1989_25_3_a13/} }
M. Utepbergenov. A method for studying regular singularities of partial differential equations. Differencialʹnye uravneniâ, Tome 25 (1989) no. 3, pp. 499-505. http://geodesic.mathdoc.fr/item/DE_1989_25_3_a13/