Sierra, M., M. Díez, F.J. Martínez, J. Fernández, and J. Aguilar. “A New Index to Evaluate Anomalies of Trace Elements in Soils: The Case of SE Spain”. Spanish Journal of Agricultural Research 7, no. 4 (December 1, 2009): 933-943. Accessed May 3, 2024. https://sjar.revistas.csic.es/index.php/sjar/article/view/1106.