Hoon Leh, Oliver Ling, Shaharuddin Ahmad, Kadaruddin Aiyub, and Yaakob Mohd Jani. 2011. “URBAN AIR ENVIRONMENTAL HEALTH INDICATORS: A PRELIMINARY SET FOR CITY OF KUALA LUMPUR”. PLANNING MALAYSIA 9 (2). https://journals.iium.edu.my/pmr/index.php/pmj/article/view/Article%209-5.