Chen, C., Q. Li, C.L. Tao, J.P. Zhai, and D.J. Tao. 2012. “Calculation of Un-Fired Carbon Content of Circulating Fluidized Bed Combustion Ash”. Asian Journal of Chemistry 24 (10):4461-64. https://asianpubs.org/index.php/ajchem/article/view/9680.