Costa, V., Konzen, E. A., & Protas, J. F. (2014). Space allowance for pigs raised in concrete flored pens and in metalic cages. Pesquisa Agropecuaria Brasileira, 18(10), 1133–1137. https://doi.org/10.1590/S1678-3921.pab1983.v18.15442