@article{1250522324,
author = {\=Okaji, Takashi},
title = {The local solvability of partial differential operator with multiple characteristics in two independent variables},
journal = {J. Math. Kyoto Univ.},
volume = {20},
number = {4},
year = {1980},
pages = { 125-140},
language = {en},
url = {http://dml.mathdoc.fr/item/1250522324}
}
Ōkaji, Takashi. The local solvability of partial differential operator with multiple characteristics in two independent variables. J. Math. Kyoto Univ., Tome 20 (1980) no. 4, pp. 125-140. http://gdmltest.u-ga.fr/item/1250522324/