Author/Creator
- Geological Survey (U.S.)522
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- United States. National Bureau of Standards157
- SPIE Digital Library150
- Lewis Research Center147
- National Institute of Standards and Technology (U.S.)137
- ebrary, Inc134
- Society of Photo-Optical Instrumentation Engineers110
- Society of Photo-optical Instrumentation Engineers107
- National Renewable Energy Laboratory (U.S.)102
- United States. Environmental Protection Agency. Office of Research and Development94
- United States. Environmental Protection Agency. Office of Air Quality Planning and Standards87
- Industrial Environmental Research Laboratory (Research Triangle Park, N.C.)80
- Goddard Space Flight Center71
- United States. Environmental Protection Agency71
- SPIE (Society)69