U.S. Environmental Protection Agency. Inventory of the U.S. greenhouse gas emissions and sinks , 1990-2010.
Chicago-viite (17. p.)U.S. Environmental Protection Agency. Inventory of the U.S. Greenhouse Gas Emissions and Sinks , 1990-2010.
MLA-viite (9. p.)U.S. Environmental Protection Agency. Inventory of the U.S. Greenhouse Gas Emissions and Sinks , 1990-2010.
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