Sampaio, Everardo Valadares de Sa Barretto, and Ignacio Hernan Salcedo. 1991. “Nutrient Cycling in Sugarcane. V. Potassium Balance During Four Cropping Periods”. Pesquisa Agropecuaria Brasileira 26 (9):1323-35. https://doi.org/10.1590/S1678-3921.pab1991.v26.3472.