CO health impact in detail
Detailed information on health impacts of carbon monoxide provided as text based information sheet of the World Health Organisation. Source: WHO Europe

 Report on US CO emissions
Long an detailed report and analysis of the carbon monoxide emissions of California and the United States (105 pages PDF from 2000)

 Vertical CO profiles
Scientific article: Vertical profiles from spaceborn observation, 2005

 CO from biomass burning
Scientific article: CO from biomass burning in the tropics; good graphs at the end of the article 2002/2003