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@article{DE_1978_14_1_a15, author = {B.-W. Schulze}, title = {Elliptic boundary value problems for operators of a special form}, journal = {Differencialʹnye uravneni\^a}, pages = {148--159}, publisher = {mathdoc}, volume = {14}, number = {1}, year = {1978}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1978_14_1_a15/} }
B.-W. Schulze. Elliptic boundary value problems for operators of a special form. Differencialʹnye uravneniâ, Tome 14 (1978) no. 1, pp. 148-159. http://geodesic.mathdoc.fr/item/DE_1978_14_1_a15/