@article{DAN_1972_205_6_a7,
     author = {\`E. Muhamadiev},
     title = {On the invertibility of elliptic partial differential operators},
     journal = {Doklady Akademii Nauk},
     pages = {1292--1295},
     publisher = {mathdoc},
     volume = {205},
     number = {6},
     year = {1972},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1972_205_6_a7/}
}