Golik, Silvina Inés, et al. “Nitrogen Accumulation, Translocation, Postanthesis Uptake and Utilization Efficiency under Different Tillage Systems and Fertlizer Types”. Pesquisa Agropecuaria Brasileira, vol. 38, no. 5, May 2003, pp. 619-26, doi:10.1590/S1678-3921.pab2003.v38.6616.