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@article{IVM_1989_11_a11, author = {S. I. Chelkak}, title = {Weak regularity of solutions of second-order elliptic quasilinear systems}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {74--84}, publisher = {mathdoc}, number = {11}, year = {1989}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1989_11_a11/} }
S. I. Chelkak. Weak regularity of solutions of second-order elliptic quasilinear systems. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 11 (1989), pp. 74-84. http://geodesic.mathdoc.fr/item/IVM_1989_11_a11/