F. L. Supian
Physics Department, Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris 35900 Perak Malaysia
Malaysia

S. W. Tho
Department of Physics, Faculty of Science and Mathematics, Sultan Idris Education University, Malaysia
Malaysia

Y. Y. Wong
Department of Physics, Faculty of Science and Mathematics, Sultan Idris Education University, Malaysia
Malaysia

M. S. Mohd Azmi
Department of Physics, Faculty of Science and Mathematics, Sultan Idris Education University, Malaysia
Malaysia

N. J. Hosman
Department of Physics, Faculty of Science and Mathematics, Sultan Idris Education University, Malaysia
Malaysia

R. Ratnawulan
Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Padang, Indonesia
Indonesia

A. F. Al Naim
Department of Physics, College of Science, King Faisal University, Saudi Arabia
Saudi Arabia