@article{GDZPPN00228832X, title = {Differential Equations without Solutions.}, journal = {Mathematische Annalen}, volume = {141}, year = {1960}, pages = {169-173}, zbl = {0093.28903}, url = {http://dml.mathdoc.fr/item/GDZPPN00228832X} }
HÖRMANDER, L. Differential Equations without Solutions.. Mathematische Annalen, Tome 141 (1960) pp. 169-173. http://gdmltest.u-ga.fr/item/GDZPPN00228832X/