Franchini, Júlio Cezar, et al. “Dynamic of Ions in Acid Soil Leached With Green Manure Residues Extracts and Pure Solutions of Organic Acids”. Pesquisa Agropecuaria Brasileira, vol. 34, no. 12, Dec. 1999, pp. 2267-76, doi:10.1590/S1678-3921.pab1999.v34.5562.