1. International Energy Agency, 2007. Tracking Industrial Energy Efficiency and CO2 Emissions. www.iea.org/publications/freepublication/tracking_emissions.pdf [accessed 15.05.15].
2. Closing the efficiency gap: barriers to the efficient use of energy;Hirst;Resour Conserv Recycl,1990
3. Internationa Energy Agency, 2012. World Energy Outlook 2012 – Executive Summary. www.iea.org/publications/freepublications/publication/English.pdf [accessed 15.05.15].
4. International Energy Agency, 2014. World Energy Outlook 2014. https://www.iea.org/publications/freepublications/publication/2014_IEA_AnnualReport.pdf [accessed 15.05.15].
5. The characteristics of energy-efficiency measures e a neglected dimension;Fleiter;Energy Policy,2012