- Cortijo, Iván., et all. "The Armorican Quartzite: when trilobites ruled the Ordovician seas of the Villuercas-Ibores-Jara UNESCO Global Geopark, Spain." Geoconservation Research (Geoconserv. Res.), vol. 4, no. 1, pp. 113-120, https://doi.org/10.30486/gcr.2021.1922890.1085