@article{DAN_1973_211_2_a5,
     author = {A. E. Merzon},
     title = {On the solvability of differential equations with constant coefficients in a cone},
     journal = {Doklady Akademii Nauk},
     pages = {285--288},
     publisher = {mathdoc},
     volume = {211},
     number = {2},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1973_211_2_a5/}
}