Ferraz, J.B.S. and Duarte, F.A. de M. 1991. Influence of non genetic factors on Large White sows productivity. Pesquisa Agropecuaria Brasileira. 26, 4 (Apr. 1991), 535–548. DOI:https://doi.org/10.1590/S1678-3921.pab1991.v26.3374.