Benevides Filho, V. de A.; Neder, N. R.; Campos, H. de; Braga Jr., R. L. C. The Use of the Microbiological Tests in the Extration of the Available Zinc of the Soils of Piracicaba Municipality . An. Esc. Super. Agr. Luiz de Queiroz 1987, 44 (1), 181-207. https://doi.org/10.1590/S0071-12761987000100009.