Hussain, Sadiq, Kanwar saleem, khurram shahzad, Niaz ahmed akhtar, and arshad chughtai. 2014. “Physical Parameters Affecting Thermal Conversion of Low-Grade Coal and Biomass for Gasification”. Journal of the Pakistan Institute of Chemical Engineers 42 (2):59-68. http://www.piche.org.pk/journal/index.php/jpiche/article/view/166.