Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1972_8_4_a4, author = {A. Ya. Khokhryakov}, title = {The degenerate periodic boundary value problem}, journal = {Differencialʹnye uravneni\^a}, pages = {607--614}, publisher = {mathdoc}, volume = {8}, number = {4}, year = {1972}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1972_8_4_a4/} }
A. Ya. Khokhryakov. The degenerate periodic boundary value problem. Differencialʹnye uravneniâ, Tome 8 (1972) no. 4, pp. 607-614. http://geodesic.mathdoc.fr/item/DE_1972_8_4_a4/