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2. California Air Resources Board (CARB) 2006 Greenhouse Gas Inventory Data-2000 to 2006 Calif. Air. Resour. Board Sacramento http://www.arb.ca.gov/app/ghg/2000_2006/ghg_sector.php
3. California Air Resources Board (CARB) 2008 California Emission Inventory Data Almanac http://www.arb.ca.gov/app/emsinv/emssumcat.php
4. California State Data Center 2003 Census 2000 Summary File 4 U.S. Census Bur. Washington, D. C. http://quickfacts.census.gov/qfd/states/06000.html