1. International Standard ISO 6976(E), Natural gas—calculation of calorific values, density, relative density and Wobbe index from composition, 1995.
2. Determination of the calorific value of natural gas by different methods
3. C.J. Cowper, in: E.R. Adlard (Ed.), Chromatography in the Petroleum Industry, Elsevier, Amsterdam, 1995.
4. C.J. Cowper, A.J. DeRose, Analysis of Gases by Chromatography, Pergamon, Oxford, 1983.
5. Simple method for the rapid analysis of natural gas by gas chromatography