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@article{DE_1994_30_7_a2, author = {V. I. Gromak and V. V. Tsegel'nik}, title = {Functional relations between solutions of equations of $P$-type}, journal = {Differencialʹnye uravneni\^a}, pages = {1118--1124}, publisher = {mathdoc}, volume = {30}, number = {7}, year = {1994}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1994_30_7_a2/} }
V. I. Gromak; V. V. Tsegel'nik. Functional relations between solutions of equations of $P$-type. Differencialʹnye uravneniâ, Tome 30 (1994) no. 7, pp. 1118-1124. http://geodesic.mathdoc.fr/item/DE_1994_30_7_a2/