Professor emeritus, University of Virginia

Professor in Applied Mathematics, University of Technology Sydney (UTS)

Professor of Mathematics, Haverford College

Associate Professor of Mathematics, Jazan University

academician, professor of Baku State University

Structural and Geotechnical Engineering, PUC de Chile

Faculty of Chemistry, Meritorious Autonomous University of Puebla

University of Illinois at Chicago

Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México

lecturer of applied mathematics,Math. Dept.;Faculty of Science, Damietta University, Egypt