On the Class of Functions Starlike with Respect to a Boundary Point

The aim of this paper is to present a new analytic characterization of the class of functions starlike with respect to a boundary point introduced by M. S. Robertson (1981, J. Math. Anal. Appl. 81, 327–345) and characterized by A. Lyzzaik (1984, Proc. Amer. Math. Soc. 91, 108–110). The method of proof, using Julia’s lemma, seems to be new.