1. International Water Research Institute University Mohammed VI Polytechnic Benguerir Morocco
2. Department of Mathematics, Faculty of Sciences University Abdelmalek Essaadi Tetouan Morocco
3. Dpto. Matemáticas Applicada, Ciencia e Ingeniería de Materiales y Tecnología Electrónica Universidad Rey Juan Carlos Móstoles‐Madrid Spain
4. Department of Engineering University of Durham Durham UK