1. T. Acar, A. Aral, H. Gonska, On Szász-Mirakyan operators preserving e2ax, a > 0. Mediterr J. Math. 14(1) (2017) 1-14.
2. M. Birou, A note about some general King-type operators. Ann Tiberiu Popoviciu Semin Funct Equ Approx Convexity. 12 (2014) 3-16.
3. W.Z. Chen, Approximation Theory of Operators, Xiamen University Publishing House. China: Xia-men, 1989.
4. Z. Ditzian, V. Totik, Moduli of Smoothness, Springer-Verlag, New York, 1987.
5. A. Erençin, S. Büyükdurakoğlu, A modification of generalized Baskakov-Kantorovich operators, Stud. Univ. Babeş-Bolyai Math. 59(3) (2014) 351-364.