Fontes, Ruy Rezende, et al. “Influence of Fertilization and Sowing Density on the Production and Quality of Dry Seeds of Pea”. Pesquisa Agropecuaria Brasileira, vol. 14, no. 4, Apr. 2014, pp. 323-7, doi:10.1590/S1678-3921.pab1979.v14.16713.