M. L. de S. Silva, G. C. Vitti, and A. R. Trevizam, “Concentration of heavy metals in grain of plants cultivated in soil with different contamination levels”, PAB, vol. 42, no. 4, pp. 527–535, Apr. 2007, doi: 10.1590/S1678-3921.pab2007.v42.7598.