dos Santos, H.P. et al. 1996. Crop rotation in Guarapuava. XV. Economic analysis of four rotation systems for wheat under no-tillage. Pesquisa Agropecuaria Brasileira. 31, 8 (Aug. 1996), 569–574. DOI:https://doi.org/10.1590/S1678-3921.pab1996.v31.4521.