Santos, Henrique Pereira dos, Ivo Ambrosi, and Itacir Sandini. 1998. “Risk Analysis of Crop Rotation Systems for Barley, over a Ten-Year Period, in No-Tillage System”. Pesquisa Agropecuaria Brasileira 33 (8):1221-27. https://doi.org/10.1590/S1678-3921.pab1998.v33.4954.