Stancu, D. D., and M. R. Occorsio. “ On Approximation by Binomial Operators of Tiberiu Popoviciu Type”. Rev. Anal. Numér. Théor. Approx., vol. 27, no. 1, Feb. 1998, pp. 167-81, https://doi.org/10.33993/jnaat271-614.