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2. [ABNT] ABNT, NBR, ISO/IEC 17025. 2005. General requirements for the competence of calibration and testing laboratories. Brazilian Association of Technical Standards
3. Bitencourt R. 2007. Uncertainty in chemical analysis: alternative approaches. Portugal: National Institute of Biological Resources. Pesticide Residue Laboratory/Directorate General for Crop Protection [LRP/DGPC]
4. [BRAZIL] Ministry of Agriculture, Livestock and Supply. 2009. National Plan of residues and contaminants in vegetal products. Normative instruction no. 21
5. [EA] European Co-operation for Accreditation. 2003. EA 4/16 guidelines on the expression of uncertainty in quantitative testing. EA Laboratory Committee