Pantoja-Timarán, F., Álvarez-Rodríguez, R., & Rodríguez-Avelló, A. S. (2005). Methods to reduce mercury pollution in small gold mining operations. Revista De Metalurgia, 41(3), 194–203. https://doi.org/10.3989/revmetalm.2005.v41.i3.205