APA (7th ed.) Citation

Cummings, T. (2013). Air quality overview. U.S. Department of Interior, National Park Service, Natural Resource Stewardship and Science.

Chicago Style (17th ed.) Citation

Cummings, Tonnie. Air Quality Overview. Fort Collins, Colorado: U.S. Department of Interior, National Park Service, Natural Resource Stewardship and Science, 2013.

MLA (9th ed.) Citation

Cummings, Tonnie. Air Quality Overview. U.S. Department of Interior, National Park Service, Natural Resource Stewardship and Science, 2013.