Conversion of units Gas Mark (Regulo) SI Units "SI Units: Temperature", U.S. National Institute of Standards and Technology (NIST), U.S. Commerce Department, February 11, 2011, web: NIST-Temp: accessed 2011-03-26.
تحويل الوحدات وحدات النظام الدولي "SI Units: Temperature", U.S. المعهد الوطني للمعايير والتقنية (NIST), U.S. Commerce Department, February 11, 2011, web: NIST-Temp: accessed 2011-03-26.