1. Universiti Putra Malaysia, Faculty of Science, Department of Physics, UPM Serdang, Selangor, Malaysia
2. Universiti Putra Malaysia, Faculty of Science, Department of Physics, UPM Serdang, Selangor, Malaysia + Universiti Putra Malaysia, Institute of Advanced Technology, Materials Synthesis and Characterization Laboratory, UPM Serdang, Selangor, Malaysia
3. nema