Md. Pisar, M., N. Hashim, R. Mat Ali, and K. L.S. “Evaluation of Piper Betle on Platelet Activating Factor (PAF) Receptor Binding Activities”. Malaysian Journal of Science, vol. 26, no. 1, Apr. 2007, pp. 79-83, https://ejournal.um.edu.my/index.php/MJS/article/view/7976.