Machado, P.L.O. de A. et al. 2006. Electrical conductivity mapping in relation to clay of a Ferralsol under no tillage system. Pesquisa Agropecuaria Brasileira. 41, 6 (Jun. 2006), 1023–1031. DOI:https://doi.org/10.1590/S1678-3921.pab2006.v41.7241.