Journal of Inequalities and Applications
Volume 2007 (2007), Article ID 83073, 10 pages
doi:10.1155/2007/83073
Research Article

Double Subordination-Preserving Properties for Certain Integral Operators

Nak Eun Cho1 and Shigeyoshi Owa2

1Department of Applied Mathematics, Pukyong National University, Pusan 608-737, South Korea
2Department of Mathematics, Kinki University, Higashi-Osaka, Osaka 577-8502, Japan

Received 27 November 2006; Revised 3 January 2007; Accepted 4 January 2007

Academic Editor: Narendra K. Govil

Copyright © 2007 Nak Eun Cho and Shigeyoshi Owa. 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.

Abstract

The purpose of the present paper is to obtain the sandwich-type theorem which contains the subordination- and superordination-preserving properties for certain integral operators defined on the space of normalized analytic functions in the open unit disk.