On the best polynomial approximation of entire transcendental functions in banach spaces. I

Vakarchuk, S. B. “On the Best Polynomial Approximation of Entire Transcendental Functions in Banach Spaces. I”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 46, no. 9, Sept. 1994, pp. 1123–1133, https://umj.imath.kiev.ua/index.php/umj/article/view/5629.