1. Adelman, M. A., 1980, Energy-income coefficients and rations: their use and abuse. Energy Economics, v. 2, no. 1, p. 2–4.
2. Berndt, E. T. and Wood, D. O., 1974, An economic interpretation of the energy-GDP ration,in M. S. Macrakis, ed., Energy: demand, conservation, and institutional problems: Cambridge, MA, MIT Press, p. 21–30.
3. BP Statistical Review of World Energy, London, The British Petroleum Co. (several issues).
4. Château, B., and Lapillonne, B., 1977. La prévision à long terme de la demande d’energie: Le modèle medée: Paris, Editions du CNRS, Collection Energie et Société, 225 p.
5. Civettini, S., 1995, The intensity of competition in the American steel industries and the strategic groups concept: Proceedings of the mineral economics and management society, fourth annual MEMS meeting, March 9–11, Boulder, Colorado, p. 50–61.