S. Buzetti, T. Muraoka, and A. O. Mauro, “Doses of zinc in different acidity conditions of a cerrado soil. I. Dry matter and grain yield and soil critical level”, PAB, vol. 26, no. 6, pp. 913–918, Jun. 1991, doi: 10.1590/S1678-3921.pab1991.v26.3422.