Starlikeness for functions of a hypercomplex variable

In this paper we introduce new notions of starlikeness for a class of functions of a hypercomplex variable. We then obtain equivalent formulations for starlikeness which resemble the analogous ones in the holomorphic case such as Nevanlinna's criterion. Furthermore we give a characterization of algebraic starlikeness in terms of non- vanishing of a suitable analog of the Hadamard product.