Pomona College, University of Illinois, Harvard University, Arizona State University …

University of Southampton

University of Padova, Guangzhou Univeristy

University of Sydney

Department of Mathematics and Statistics, College of Science, Taif University, PO Box …

Associate Professor

Emeritus Professor of Mathematics, York University UK

University of North Carolina Wilmington and Northn Illinois University

Assistant Professor, Math. Dept, King Khalid University, KSA. , and Al-Azhar University،Egy.

Retired