Carvalho, O. S., Saa, A., Montes, J. M. G., Caballero, R., & López, F. G. (1999). Temporal variability of chemical properties in a soil with three cultivation systems. Pesquisa Agropecuária Brasileira, 34(12), 2299–2309. https://doi.org/10.1590/S1678-3921.pab1999.v34.5566