Bakke, Ivonete Alves, et al. “Forage Yield and Quality of a Dense Thorny and Thornless ‘jurema-Preta’ Stand”. Pesquisa Agropecuaria Brasileira, vol. 42, no. 3, Mar. 2007, pp. 341-7, doi:10.1590/S1678-3921.pab2007.v42.7573.