de Faria, C.M.B. and Pereira, J.R. 1992. Sources and levels of nitrogen and onion yield in the submedio São Francisco region. Pesquisa Agropecuaria Brasileira. 27, 3 (Mar. 1992), 403–407. DOI:https://doi.org/10.1590/S1678-3921.pab1992.v27.3662.