Eira, Paulo Augusto da, et al. “Comparison of Experimental Design in a Field Trial on Fertilization of Black Beans (<i> Phaseolus vulgaris< I> )”. Pesquisa Agropecuaria Brasileira, vol. 8, no. 7, Apr. 2014, pp. 121-5, doi:10.1590/S1678-3921.pab1973.v8.17432.