JananiT., and YalçınS. “Initial Seven Coefficient Estimates for a Subclass of Bi-Starlike Functions”. Ukrains’kyi Matematychnyi Zhurnal 73, no. 11 (November 23, 2021): 1576 - 1584. Accessed November 21, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/1046.