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@article{DE_1992_28_5_a9, author = {S. Baizaev and \`E. Muhamadiev}, title = {On the index of first-order elliptic operators in the plane}, journal = {Differencialʹnye uravneni\^a}, pages = {818--827}, publisher = {mathdoc}, volume = {28}, number = {5}, year = {1992}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1992_28_5_a9/} }
S. Baizaev; È. Muhamadiev. On the index of first-order elliptic operators in the plane. Differencialʹnye uravneniâ, Tome 28 (1992) no. 5, pp. 818-827. http://geodesic.mathdoc.fr/item/DE_1992_28_5_a9/