Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DAN_1988_303_1_a3, author = {S. Z. Levendorskii}, title = {Types of degenerate elliptic operators}, journal = {Doklady Akademii Nauk}, pages = {24--28}, publisher = {mathdoc}, volume = {303}, number = {1}, year = {1988}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1988_303_1_a3/} }
S. Z. Levendorskii. Types of degenerate elliptic operators. Doklady Akademii Nauk, Tome 303 (1988) no. 1, pp. 24-28. http://geodesic.mathdoc.fr/item/DAN_1988_303_1_a3/