@article{DAN_1975_220_5_a0,
     author = {N. K. Bliev},
     title = {On a class of elliptic systems of first-order differential equations},
     journal = {Doklady Akademii Nauk},
     pages = {1001--1003},
     publisher = {mathdoc},
     volume = {220},
     number = {5},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1975_220_5_a0/}
}