1. Faculty of Applied Sciences, Universiti Teknologi MARA, Shah Alam, Selangor, Malaysia
2. Chemistry Section, School of Distance Education, Universiti Sains Malaysia, Minden, Penang, Malaysia
3. Faculty of Applied Sciences, Universiti Teknologi MARA, Arau, Perlis, Malaysia
4. Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
5. Department of Chemistry, College of Sciences for Women, Baghdad University, Baghdad, Iraq