Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DAN_1972_204_5_a2, author = {S. G. Gindikin}, title = {Differential operators with real characteristics of high order}, journal = {Doklady Akademii Nauk}, pages = {1037--1040}, publisher = {mathdoc}, volume = {204}, number = {5}, year = {1972}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1972_204_5_a2/} }
S. G. Gindikin. Differential operators with real characteristics of high order. Doklady Akademii Nauk, Tome 204 (1972) no. 5, pp. 1037-1040. http://geodesic.mathdoc.fr/item/DAN_1972_204_5_a2/