@article{1195514371, author = {Morimoto, Yoshinori}, title = {On a criterion for hypoellipticity}, journal = {Proc. Japan Acad. Ser. A Math. Sci.}, volume = {62}, number = {6}, year = {1986}, pages = { 137-140}, language = {en}, url = {http://dml.mathdoc.fr/item/1195514371} }
Morimoto, Yoshinori. On a criterion for hypoellipticity. Proc. Japan Acad. Ser. A Math. Sci., Tome 62 (1986) no. 6, pp. 137-140. http://gdmltest.u-ga.fr/item/1195514371/