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@article{IVM_1976_6_a5, author = {A. I. Ko\v{s}elev}, title = {The smoothness of the solutions of second order quasilinear elliptic systems}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {45--61}, publisher = {mathdoc}, number = {6}, year = {1976}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1976_6_a5/} }
A. I. Košelev. The smoothness of the solutions of second order quasilinear elliptic systems. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 6 (1976), pp. 45-61. http://geodesic.mathdoc.fr/item/IVM_1976_6_a5/