Author
United States. Environmental Protection Agency. Office of Air Quality Planning and Standards
46
United States. Environmental Protection Agency. Office of Air and Radiation,
37
Colorado. Air Pollution Control Division
36
United States. Environmental Protection Agency. Health and Environmental Impacts Division,
29
Colorado. Air Quality Control Commission
28
United States. Environmental Protection Agency. Office of Mobile Sources,
28
United States. Environmental Protection Agency,
24
United States. Environmental Protection Agency. Office of Air and Radiation
23
United States. Environmental Protection Agency
22
United States. Environmental Protection Agency. Office of Air Quality Planning and Standards,
21
United States. Congress. Senate. Committee on Environment and Public Works,
18
Small Business Assistance Program (Colo.)
16
United States. Congress. Senate. Committee on Environment and Public Works
16
United States. Environmental Protection Agency. Office of Mobile Source Air Pollution Control. Emission Control Technology Division,
16
United States. Environmental Protection Agency. Office of Mobile Source Air Pollution Control. Emission Control Technology Division. Technology Assessment and Evaluation Branch,
16
Library of Congress. Congressional Research Service,
15
National Renewable Energy Laboratory (U.S.)
15
ScienceDirect (Online service)
15
United States. Environmental Protection Agency. Emission Standards Division
14
United States. Environmental Protection Agency. Office of Transportation and Air Quality,
14
United States. Congress. Senate. Committee on Environment and Public Works. Subcommittee on Clean Air and Nuclear Safety,
13
United States. Environmental Protection Agency. Air Quality Assessment Division,
13
SpringerLink (Online service)
12
Air and Energy Engineering Research Laboratory
11
United States. Environmental Protection Agency. Office of Mobile Source Air Pollution Control. Emission Control Technology Division. Standards Development and Support Branch,
10
United States. Environmental Protection Agency. Office of Mobile Source Air Pollution Control. Emission Control Technology Division. Test and Evaluation Branch,
9
United States. Environmental Protection Agency. Office of Mobile Sources. Test and Evaluation Branch,
9
United States. Environmental Protection Agency. Office of Transportation and Air Quality. Assessment and Standards Division,
9
United States. Environmental Protection Agency. Transportation and Climate Division,
9
Motor Vehicle Emission Laboratory (U.S.),
8
United States. Environmental Protection Agency. Office of Air Quality Planning and Standards. Information Transfer and Program Integration Division
8
Eastern Research Group, Inc
7
Regional Air Quality Council (Colo.)
7
United States. Environmental Protection Agency. Transportation and Regional Programs Division,
7
Glover, Edward L.,
6
McCarthy, James E. (Specialist in environmental policy),
6
National Risk Management Research Laboratory (U.S.)
6
United States. Congress. Senate. Committee on Foreign Relations
6
United States. Environmental Protection Agency. Emissions, Monitoring, and Analysis Division
6
United States. Environmental Protection Agency. Office of Mobile Sources. Emission Control Technology Division,
6
United States. Environmental Protection Agency. Science Advisory Board
6
Colorado. Department of Regulatory Agencies. Office of Policy, Research, and Regulatory Reform
5
Esworthy, Robert,
5
Lattanzio, Richard K.,
5
Midwest Research Institute (Kansas City, Mo.)
5
Samet, Jonathan M.
5
Sierra Research (Firm)
5
United States. Congressional Budget Office
5
United States. Environmental Protection Agency. Assessment and Modeling Division,
5
United States. Environmental Protection Agency. Clean Air Markets Division
5
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