Couto, Rafael da Rosa, et al. “Microbiological and Chemical Attributes of a Hapludalf Soil With Swine Manure Fertilization”. Pesquisa Agropecuaria Brasileira, vol. 48, no. 7, Oct. 2013, pp. 774-82, doi:10.1590/S1678-3921.pab2013.v48.13936.