Witter, S. and Blochtein, B. 2003. Effect of pollination by bees and other insects on the production of onion seeds. Pesquisa Agropecuaria Brasileira. 38, 12 (Dec. 2003), 1399–1407. DOI:https://doi.org/10.1590/S1678-3921.pab2003.v38.6717.