Gutierrez, Nestor, et al. “Small Ruminant Exploitation in Ceará State. A Vision of Capital, Income and Costs”. Pesquisa Agropecuaria Brasileira, vol. 24, no. 5, Apr. 2014, pp. 509-16, https://doi.org/10.1590/S1678-3921.pab1989.v24.15778.