Patterson, Richard F., and Ekrem Savas. “Korovkin and Weierstrass Approximation via Lacunary Statistical Sequences”. Journal of Mathematics and Statistics, vol. 1, no. 2, 2005, pp. 165-7, https://doi.org/10.3844/jmssp.2005.165.167.
Patterson, R. F., & Savas, E. (2005). Korovkin and Weierstrass Approximation via Lacunary Statistical Sequences. Journal of Mathematics and Statistics, 1(2), 165-167. https://doi.org/10.3844/jmssp.2005.165.167
Patterson RF, Savas E. Korovkin and Weierstrass Approximation via Lacunary Statistical Sequences. Journal of Mathematics and Statistics. 2005;1(2):165-7.