中国科学院数学与系统科学研究院期刊网
AMS
Pointwise Simultaneous Approximation by Combinations of Baskakov Operators
Lin Sen XIE, Zhong Rui SHI
Acta Mathematica Sinica . 2007, (5): 935 -944 .  DOI: 10.1007/s10114-005-0827-7