1. Handbook of Industrial Energy Analysis;Boustead,1979
2. The energy costs of goods and services;Bullard;Energy Policy,1975
3. CBS, 1996. Gebruikershandboek budgetonderzoek 1994 (in Dutch, User manual budget surveys). Report of Central Office of Statistics, Heerlen/Voorburg, The Netherlands.
4. Calculating the energy requirements of household purchases—a practical step by step method;Engelenburg;Energy Policy,1994
5. Eurostat, 1993. Energy consumption in households. Report by Eurostat, Luxembourg.