@article{MAT_1961_5_5_a5,
     author = {L. V. H\"ormander},
     title = {Differential equations without solutions},
     journal = {Matematika},
     pages = {115--120},
     publisher = {mathdoc},
     volume = {5},
     number = {5},
     year = {1961},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MAT_1961_5_5_a5/}
}