F. Wittwer, O. Araya, A. Ceballos, and H. Böhmwald, “Mineral concentration in forage and bovine exposed to the eruption of Lonquimay volcano”, PAB, vol. 32, no. 6, pp. 655–661, Jun. 1997, doi: 10.1590/S1678-3921.pab1997.v32.4695.