MOHD ZULKIFLI HASSAN, ADI IRFAN CHE ANI , NOR RIMA MUHAMAD ARIFF. 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, v. 29, n. 7s, p. 375 - 382, 14 Apr. 2020.