U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Western Ecology Division,

Lewis Publishers,

Lewis Publishers,

U.S. Dept. of the Interior, U.S. Geological Survey,

The Service : For sale by the Supt. of Docs., U.S. G.P.O.,

U.S. Environmental Protection Agency, Office of Water, Office of Wetlands, Oceans, and Watersheds : For sale by the U.S. G.P.O., Supt. of Docs.,

Fish and Wildlife Service, U.S. Dept. of the Interior ; for sale by the Supt. of Docs., U.S. Govt. Print. Off.,