International Journal of Mathematics and Mathematical Sciences
Volume 6 (1983), Issue 2, Pages 335-340
doi:10.1155/S0161171283000290
Abstract
We consider for α>0, the convex combinations f(z)=(1−α)F(z)+αzF′(z), where F belongs to different subclasses of univalent functions and find the radius for which f is in the same class.