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@article{CM_1959-1960__14__41_0, author = {Ostrowski, A. M.}, title = {Three theorems on products of power series}, journal = {Compositio Mathematica}, pages = {41--49}, publisher = {Kraus Reprint}, volume = {14}, year = {1959-1960}, mrnumber = {107113}, zbl = {0092.29303}, language = {en}, url = {http://geodesic.mathdoc.fr/item/CM_1959-1960__14__41_0/} }
Ostrowski, A. M. Three theorems on products of power series. Compositio Mathematica, Tome 14 (1959-1960), pp. 41-49. http://geodesic.mathdoc.fr/item/CM_1959-1960__14__41_0/