Kerk, Lee Chang, Nurkhairany Amyra Mokhtar, Palaniappan Shamala, and Basri Badyalina. “Global Optimization Method For Minimizing Portfolio Selection Risk”. MATEMATIKA: Malaysian Journal of Industrial and Applied Mathematics 38, no. 2 (August 15, 2022): 115–123. Accessed October 6, 2022. https://matematika.utm.my/index.php/matematika/article/view/1403.