Mohd Zulkifli Hassan, Adi Irfan Che Ani , Nor Rima Muhamad Ariff. 2020. “The Correlation Between External Factors and Housing Developers’ Involvement in Affordable Housing: An Importance-Performance Matrix Analysis (IPMA)”. International Journal of Advanced Science and Technology 29 (7s), 375 -82. http://sersc.org/journals/index.php/IJAST/article/view/9451.