"epa-450-r-12-001" . "Report to Congress on Black Carbon EPA-450/R-12-001"^^ . "2012"^^ . "http://www.epa.gov/blackcarbon/2012report/fullreport.pdf"^^ . "report" . . . . . . . _:genid1 . _:genid1 . _:genid1 . _:genid1 . _:genid2 . _:genid2 . _:genid2 . _:genid2 . _:genid3 . _:genid3 . _:genid3 . _:genid3 . _:genid4 . _:genid4 . _:genid4 . _:genid4 . _:genid5 . _:genid5 . _:genid5 . _:genid5 . _:genid6 . _:genid6 . _:genid6 . _:genid6 .