Silva, Carlos Alberto, and Fabiano Ribeiro do Vale. “Nitrate Availability in Brazilian Soils under Effect of Liming and Sources and Amounts of Nitrogen”. Pesquisa Agropecuaria Brasileira, vol. 35, no. 12, Dec. 2000, pp. 2461-7, doi:10.1590/S1678-3921.pab2000.v35.6042.