@article{DE_1995_31_1_a9,
     author = {V. E. Balabaev},
     title = {First-order normal elliptic systems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {71--83},
     publisher = {mathdoc},
     volume = {31},
     number = {1},
     year = {1995},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1995_31_1_a9/}
}