Mocanu, P. T., Ripeanu, D., & Şerb, I. (1981). On the order of starlikeness of convex functions of order \(\alpha\). Anal. Numér. Théor. Approx., 10(2), 195–199. Retrieved from https://ictp.acad.ro/jnaat/journal/article/view/1981-vol10-no2-art8