ROUCHE TYPE THEOREMS AND A THEOREM OF ADAMYAN, AROV AND KREIN

摘要

We show Rouche type theorems using a theorem of Adamyan, Arov and Krcin. As applications, we obtain a certain characterization of self-maps of the unit disc in terms of the location of the Denjoy-Wolf point and we study a function in the Smirnov class whose real part is positive.