![]() | American Chemical Society www.acs.org |
![]() | American National Standards Institute (ANSI) www.ansi.org |
![]() | American Society for Testing and Materials (ASTM) www.astm.org |
![]() | American Society of Quality Control (ASQC) www.asq.org |
![]() | Association of Official Agricultural Chemists www.aoac.org |
![]() | Avaliação da Conformidade European Organization for Testing and Certification |
![]() | Bureau International des Poids et Mesures www.bipm.fr |
![]() | Chemical Abstracts Service (CAS) www.cas.org |
![]() | COMAR - The Database for Certified Reference Materials www.bam.de |
![]() | Comitê Consultivo para Quantidade de Matéria Substance - CCQM www.bipm.fr |
![]() | Co-Operation on International Traceability in Analytical Chemistry - CITAC www.irmm.jrc.be |