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@article{CM_1990__74_3_327_0, author = {Yang, Zi-Xiao and Li, Bu-Xi}, title = {On restricted derivative approximation}, journal = {Compositio Mathematica}, pages = {327--331}, publisher = {Kluwer Academic Publishers}, volume = {74}, number = {3}, year = {1990}, mrnumber = {1055699}, zbl = {0697.41002}, language = {en}, url = {http://geodesic.mathdoc.fr/item/CM_1990__74_3_327_0/} }
Yang, Zi-Xiao; Li, Bu-Xi. On restricted derivative approximation. Compositio Mathematica, Tome 74 (1990) no. 3, pp. 327-331. http://geodesic.mathdoc.fr/item/CM_1990__74_3_327_0/