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Washington, D.C. : U.S. Environmental Protection Agency, Office of Research and Development ; Corvallis, Or. : Environmental Research Laboratory ; Las Vegas, NV : Environmental Monitoring Systems Laboratory, 
"A contribution to the National Acid Precipitation Assessment Program"., "EPA/600/8-90/055"., and "Funded wholly or in part by the U.S. Environmental Protection Agency under contract no. 68-03-3249 to Lockheed Engineering and Management Services Company, Inc."--p. ii.