R. Montanari, J. M. Júnior, G. T. Pereira, and Z. M. de Souza, “Landscape form as a criterion for sampling optimization of an oxisol under cultivation of sugar cane”, PAB, vol. 40, no. 1, pp. 69–77, Jan. 2005, doi: 10.1590/S1678-3921.pab2005.v40.6923.