1. ASTM D 7042-04 (2004). Viscosidade Dinâmica e Densidade de Líquidos pelo Viscosímetro Stabinger (Cálculo da Viscosidade Dinâmica);ASTM International:West Conshohocken, PA, USA, 2004; www.astm.org.
2. Government of Alberta, Canada;www.gov.ab.ca(accessed Feb 15, 2014).
3. U.S. Department of Energy;www.energy.gov(accessed Feb 15, 2014).
4. Organization of the Petroleum Exporting Countries;http://www.opec.org/opec_web/en/(accessed Feb 15, 2014).