1. Transport energy consumption and emissions – Statistics Explained.EUROSTAT:Luxembourg,http://epp.eurostat.ec.europa.eu/statistics_explained/index.php/Transport_energy_consumption_and_emissions.
2. Greenhouse Gas Inventory Data Explorer,Environmental Protection Agency;https://www3.epa.gov/climatechange/ghgemissions/inventoryexplorer/index.html#transportation/allgas/source/all.
3. The Norwegian scenario and action plan presented by NITO Future Climate - Engineering solutions.NITO:Oslo, 2009; p41;http://www.fc-es.net/wp-content/themes/fces/uploads/2012/08/National-Climate-Plan-Norway-Phase-1.pdf.