Raşa, I. “On the Monotonicity of Sequences of Bernstein-Schnabl Operators”. Anal. Numér. Théor. Approx. 17, no. 2 (August 1, 1988): 185–187. Accessed April 14, 2025. https://ictp.acad.ro/jnaat/journal/article/view/1988-vol17-no2-art12.