Zucchi, O. L. A. D. and Nascimento Filho, V. F. do (1995) “Qualitative and quantitative characterization of elements by X-ray fluorescence technique in mineral supplement for livestock. I. Wavelength dispersion”, Pesquisa Agropecuaria Brasileira, 30(12), pp. 1427–1439. doi: 10.1590/S1678-3921.pab1995.v30.4443.