Proceedings : progress evaluation meeting, pollution of Lake Erie and its tributaries: Indiana, Michigan, New York, Ohio, Pennsylvania.

[Washington] : U.S. Federal Water Pollution Control Administration, 1969

Proceedings, Nov. 13, Burlington Vt., Dec. 19-20, 1969, Boston, Mass.

Washington, D.C. : U.S. Dept. of the Interior : Federal Water Pollution Control Administration, 1969

Proceedings : second session, Boston, Massachusetts, Wednesday, April 30, 1969.

[Washington] : U.S. Federal Water Pollution Control Administration, 1969

Transcript of proceedings : sixth session.

Washington : [U. S. Federal Water Pollution Control Administration], 1967

Proceedings.

[Washington] : U. S. Dept. of Interior, Federal Water Pollution Control Administration, 1966

Proceedings.

[Washington] : U. S. Dept. of the Interior, Federal Water Pollution Control Administration, 1968

Proceedings /

[Washington, D.C.] : U.S. Dept. of the Interior, Federal Water Pollution Control Administration, 1967

Proceedings.

[Washington] : U.S. Dept. of the Interior, Federal Water Pollution Control Administration, 1968

Proceeding : May 13-14-15, 1969, Duluth, Minnesota, executive session, September 30-October 1, 1969, Duluth, Minnesota, Conference - Pollution of Lake Superior and its Tributary Ba...

[Washington, D.C.] : Federal Water Pollution Control Administration, 1970

Conference in the Matter of Pollution of the Interstate Waters of Perdido Bay and Its Tributaries (Florida-Alabama) : proceedings.

Washington : U.S. Federal Water Pollution Control Administration, 1970

Transcript of proceedings.

[Washington] : U.S. Federal Water Pollution Control Administration, 1969

Conference on the Matter of Pollution of Lake Michigan and Its Tributary Basins : held in Chicago, Illinois ... 1968 : transcript of proceedings.

Washington, D.C. : Federal Water Pollution Control Administration, 1968

Proceedings.

[Washington] : U.S. Federal Water Pollution Control Administration, 1970

Proceedings.

[Washington] : U.S. Dept. of the Interior, Federal Water Pollution Control Administration, 1966

Transcript of proceedings.

[Washington] : [U.S. Federal Water Pollution Control Administration], 1970

Proceedings: [third session]

Washington : U.S. Federal Water Pollution Control Administration, 1969

Proceedings : May 20, 1968, Boston, Massachusetts : Conference, pollution of the navigable waters of Boston Harbor and its tributaries.

[Washington] : U.S. Dept. of the Interior, Federal Water Pollution Control Administration, 1968

Proceedings: third session.

[Washington] : U.S. Federal Water Pollution Control Administration, 1969

Proceedings, 2nd session.

[Washington] : U.S. Federal Water Pollution Control Administration, 1969