Sources and Resources for Planes, Trains, and Automobiles: Comparing the CO2 Impacts


U.S. National Transportation Statistics, Chapter 4, "Transportation, Energy, and the Environment,"


U.K. Department of Environment, Food, and Rural Affairs, "2008 Guidelines to Defra's GHG Conversion Factors: Methodology Paper for Transport Emission Factors," July 2008,


The Climate Registry, "General Reporting Protocol, Table 13.1 - U.S. Default CO2 Emission Factors for Transport Fuels,", "Find and compare cars,"