Journal of Inequalities and Applications
Volume 2008 (2008), Article ID 859105, 14 pages
Research Article

A Class of Integral Operators Preserving Subordination and Superordination

Nak Eun Cho and In Hwa Kim

Department of Applied Mathematics, Pukyong National University, Pusan 608-737, South Korea

Received 30 October 2007; Accepted 8 January 2008

Academic Editor: Donal O'Regan

Copyright © 2008 Nak Eun Cho and In Hwa Kim. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We give some subordination- and superordination-preserving properties of certain nonlinear integral operators defined on the space of normalized analytic functions in the open unit disk. The sandwich-type theorems for these integral operators are also obtained. Moreover, we consider an application of the subordination and superordination theorems to the Gauss hypergeometric function.