Distribution of 'ANTPOT.14 C'-Atrazine residues in humus fractions of a brazilian soil - Monteiro, Regina Teresa Rosim; Burauel, P; Tornisielo, Valdemar Luiz; Queiroz, Brígida Pimentel Villar de; Cella, Antonio Carlos (International Symposium on Environmental Biogeochemistry, 1997)