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@article{IVM_1970_10_a0, author = {M. A. Akivis}, title = {The structure of conjugate systems on multidimensional surfaces}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {3--11}, publisher = {mathdoc}, number = {10}, year = {1970}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1970_10_a0/} }
M. A. Akivis. The structure of conjugate systems on multidimensional surfaces. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 10 (1970), pp. 3-11. http://geodesic.mathdoc.fr/item/IVM_1970_10_a0/