Horowitz, Arão, and Humberto da Silveira Dantas. 2014. “The Geochemistry of Minor Elements in Pernambuco Soils. II. Cobalt in the ‘Zona Litoral-Mata’”. Pesquisa Agropecuaria Brasileira 3 (1):173-82. https://doi.org/10.1590/S1678-3921.pab1968.v3.17890.