de Sousa Gurgel, G.C. et al. 2016. Ammonia volatilization from mixed mineral fertilizers containing urea. Pesquisa Agropecuaria Brasileira. 51, 9 (Oct. 2016), 1686–1694. DOI:https://doi.org/10.1590/S1678-3921.pab2016.v51.22477.