Carvalho, M. M., Freitas, V. de P., & Filho, A. B. da C. (1994). Phosphorus requirements for the establishment of two forage grasses in an acid soil. Pesquisa Agropecuaria Brasileira, 29(2), 199–210. https://doi.org/10.1590/S1678-3921.pab1994.v29.4045