Yusoff M.S, Meor, Hairunazifah Maarop, Muhd Noorul Ehsan, and Hishamuddin Harun. 2002. “Development of a Nondestructive Quantitative Procedure for the Analysis of Gold in Jewellery”. Malaysian Journal of Science 21 (December):27-30. https://samudera.um.edu.my/index.php/MJS/article/view/8853.