AMPES - Asociación Mexicana de Proveedores de Estaciones de Servicio A.C.  www.ampes.com.mx

APLMF - Asia Pacific Legal Metrology Forum  www.aplmf.org

BIPM -  Bureau International des Poids et Mesures  www.bipm.org

OIML - International Organization of Legal Metrology  www.oiml.org

SIM   - Sistema Interamericano de Metrologia  www.sim-metrologia.org.br

API - American Petroleum Institute http://api-ec.api.org

NIST - National Institute of Standards and Technology  http://ts.nist.gov/ts/htdocs/230/235/owmhome.htm

PEI    - Petroleum Equipment Institute  www.pei.org