Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1975_11_2_a22, author = {I. P. Martynov}, title = {A generalization of a theorem of {H.} {Wittich}}, journal = {Differencialʹnye uravneni\^a}, pages = {388--389}, publisher = {mathdoc}, volume = {11}, number = {2}, year = {1975}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1975_11_2_a22/} }
I. P. Martynov. A generalization of a theorem of H. Wittich. Differencialʹnye uravneniâ, Tome 11 (1975) no. 2, pp. 388-389. http://geodesic.mathdoc.fr/item/DE_1975_11_2_a22/