Prego, R., P. Ferro, and C. Trujillo. “Lead and Zinc contamination of surface sediments in the main harbours of the Galician Rias”. Journal of Iberian Geology, vol. 34, vol. 34, no. 2, 2008, pp. 243-52, https://revistas.ucm.es/index.php/JIGE/article/view/JIGE0808220243A.