Geological controls on mineralogy and geochemistry of the Late Permian coals in the Liulong Mine of the Liuzhi Coalfield, Guizhou Province, Southwest China
Li, B., Zhuang, X., Li, J., Querol, X., Font, O. and Moreno, N. International Journal of Coal Geology 154, 1-15. http://dx.doi.org/10.1016/j.coal.2015.12.003