[1]  Chang G. Generalized Bernstein-B\'ezier polynomial. J Comput  Math, 1983, 1(4): 322--327

[2]  Ditzian  Z, Ivanov K. Bernstein-type operators and their derivatives. J Approx Theory, 1989, 56: 72--90

[3]  Ditzian Z, Totik V. Moduli of Smoothness. New York: Springer-Verlag, 1987

[4] Guo S,  Liu L,  Qi Q. Pointwise estimate for linear combinations of Bernstein-Kantorovich operators. J Math  Anal Appl, 2002, 265: 135--147

[5] Zeng X. On the rate of the convergence of the generalized Szasz type operators for functions of bounded variation. J Math Anal Appl, 1998,  226: 309--325

[6] Zeng X,  Chen W. On the rate of convergence of the generalized Durrmeyer type operators for functions of bounded variation. J Approx Theory, 2000, 102: 1--12

[7]  Zeng  X, Piriou A. On the rate of convergence of two Bernstein-Bézier type operators for bounded variation functions. J Approx Theory, 1998, 95: 369--387