Second Hankel Determinant for a Bi-univalent Function Subclass Based Gegenbauer (Ultraspherical) Polynomials. Eur. J. Pure Appl. Math. [Internet]. 2025 May 1 [cited 2025 Dec. 5];18(2):5968. Available from: https://www.ejpam.com/index.php/ejpam/article/view/5968