Four different methods for extraction of total and available Zn, Cd, Fe, Mn and Cu in soil were compared by V. Ivezic et al. (2013). Detailed methods of the extraction and analysis of these elements in soil are available in the following article:
Ivezic V, Loncaric Z,, Engler M, Kerovec D and Singh BR (2013) Comparison of different extraction methods representing available and total concentration of Cd, Cu, Fe, Mn and Zn in Soil. POLJOPRIVREDA 19(1): 53-58.
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