Xu, Chunning; He, Jiaxing On derivation approximation of Sikkema-Bernstein operator. (Chinese) Zbl 0826.41024 J. Math. Res. Expo. 14, No. 1, 153-154 (1994). MSC: 41A36 Approximation by positive operators Keywords:Sikkema-Bernstein operator × Cite Format Result Cite Review PDF