Terrell, D.J. et al. 1978. Geochemistry of some metamorphic and sedimentary rocks from the mineral district of Zacatecas, Zac., México. Geofísica Internacional. 17, 2 (abr. 1978), 155–166. DOI:https://doi.org/10.22201/igeof.00167169p.1978.17.2.930.