Younglove, B. A.; Ely, J. F. (1987), "Thermophysical Properties of Fluids II Methane, Ethane, Propane, Isobutane, and Normal Butane", Journal of Physical and Chemical Reference Data, 16 (4): 577, Bibcode:1987JPCRD..16..577Y, doi:10.1063/1.555785, ISSN0047-2689
Younglove, B. A.; Ely, J. F. (1987), "Thermophysical Properties of Fluids II Methane, Ethane, Propane, Isobutane, and Normal Butane", Journal of Physical and Chemical Reference Data, 16 (4): 577, Bibcode:1987JPCRD..16..577Y, doi:10.1063/1.555785, ISSN0047-2689
Younglove, B. A.; Ely, J. F. (1987), "Thermophysical Properties of Fluids II Methane, Ethane, Propane, Isobutane, and Normal Butane", Journal of Physical and Chemical Reference Data, 16 (4): 577, Bibcode:1987JPCRD..16..577Y, doi:10.1063/1.555785, ISSN0047-2689