Professor of Mathematics, Berlin University of Applied Sciences and Technology, Germany

Associate Professor, Eastern Mediterranean University and Sultan Qaboos University

Institute of Mathematics and Informatics, Bulgarian Academy of Sciences

University of Douala, Higher National Polytechnic School

School of Liberal Arts, Seoul National University of Science and Technology

Universidad Autónoma de la Ciudad de México (UACM)

Department of Mathematics, Faculty of Science, Kuwait University

Faculty of Computer Science, Goce Delcev University, Stip, N. Macedonia