Noramly, Glenda, Azhar bin Hussin, Chong, V. C, and Phang, Siew Moi. 2005. “The Scientific, Social, Environmental and Economic Value of N.E. Langkawi: An Overview of the Present Status”. Malaysian Journal of Science 24 (April):219-35. https://ejournal.um.edu.my/index.php/MJS/article/view/8848.