Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DAN_1971_200_3_a18, author = {A. B. Shvartsburg}, title = {Transition lines and singular points in nonlinear geometric optics equations}, journal = {Doklady Akademii Nauk}, pages = {575--578}, publisher = {mathdoc}, volume = {200}, number = {3}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1971_200_3_a18/} }
A. B. Shvartsburg. Transition lines and singular points in nonlinear geometric optics equations. Doklady Akademii Nauk, Tome 200 (1971) no. 3, pp. 575-578. http://geodesic.mathdoc.fr/item/DAN_1971_200_3_a18/