"http://physics.nist.gov/Pubs/SP811/appenB9.html"^^ . . . "\\(\\textit{British Thermal Unit}\\) (BTU or Btu) is a traditional unit of energy equal to about \\(1.0550558526 \\textit{ kilojoule}\\). It is approximately the amount of energy needed to heat 1 pound (0.454 kg) of water from \\(39 \\,^{\\circ}{\\rm F}\\) to \\(40 \\,^{\\circ}{\\rm F}\\) . The unit is most often used in the power, steam generation, heating and air conditioning industries. In scientific contexts the BTU has largely been replaced by the SI unit of energy, the \\(joule\\), though it may be used as a measure of agricultural energy production (BTU/kg). It is still used unofficially in metric English-speaking countries (such as Canada), and remains the standard unit of classification for air conditioning units manufactured and sold in many non-English-speaking metric countries."^^ . . . . "[Btu_IT]"^^ . "British Thermal Unit (International Definition)"@en . "http://www.knowledgedoor.com/2/units_and_constants_handbook/british-thermal-unit_group.html"^^ . "1055.05585262"^^ . "http://www.iso.org/iso/home/store/catalogue_ics/catalogue_detail_ics.htm?csnumber=31890"^^ . . "http://en.wikipedia.org/wiki/British_thermal_unit"^^ . . "Btu{IT}" . . "BTU" .