Quesada, O., J. C. Llópiz, E. Martínez, K. Otero, R. M. Acosta, and W. Ricardo. “Cuban Barite Characterization and Its Carbothermic Reduction in Microwave Oven”. Revista De Metalurgia, vol. 43, no. 6, Dec. 2007, pp. 458-63, doi:10.3989/revmetalm.2007.v43.i6.88.