Castro, A. F. de, Barreto, W. de O., & Anastácio, M. de L. A. (2014). Correlations between pH and per cent base saturation of some Brazilian soils. Pesquisa Agropecuaria Brasileira, 7(6), 9–17. https://doi.org/10.1590/S1678-3921.pab1972.v7.17337