Arizona Public Service
P.O. Box 2591
Phoenix, Arizona 85002

Hawaiian Electric Company, Inc.
Box 2750
Honolulu, Hawaii 96803

Arkansas Power and Light
P.O. Box  6869
Pine Bluff, Arkansas 71601

Central Illinois Company
300 Liberty Street
Peoria, Illinois 61602

Central Illinois Public Service
607 E. Adams
Springfield, Illinois 62701

Dept. of Water & Power
City of Los Angeles
111 North Hope Street
Los Angeles, California 92112

San Diego Gas & Electric
P.O. Box 1831
San Diego, California 92112

Calgary Power Limited
Box 1900
Calgary 2, Alberta
Canada

Iowa Southern Utilities
3000 Sheridan Avenue
Centerville, Iowa 52544

Hydro-Quebec
Montreal
Canada

Public Service Company of Colorado
550 - 15th Street
Denver, Colorado 80201

Kansas Power & Light Company
818 Kansas Avenue
Topeka, Kansas 66603

Delmarva Power & Light
630 West Front Street
Wilmington, Delaware 19899

New England Electric Service
441 Stuart Street
Boston, Massachusetts 02116

Eugene Water & Electric Broad
500 East 4th Avenue
Eugene, Oregon 97401

Boston Edison
800 Boylston Street Boston, Massachusetts 02199

GM Engineering Staff
GM Technical Center
Warren, Michigan 48090

Pennsylvania Power & Light
901 Hamilton Street
Allen Town, Pennsylvania 18101

Mr. D. S. Gilmore
1219 Short Road
Kalamazoo, Michigan 49001

Philadelphia Electric
1000 Chestnut Street
Philadelphia, Pennsylvania 19105

Bendix Corp., Aerospace Systems.
3300 Plymouth Road
Ann Arbor, Michigan 48105

Eagle Picher Industries Inc.
P.O. Box 47
Joplin, Missouri 64801

Puerto Rico Water Resources Authority
San Juan, Puerto Rico 00936

Atlantic City Electric Company
1600 Pacific Avenue
Atlantic City, New Jersey 08404

Swedish State Power Board
Fack Vallingby 1
Stockholm, Sweden

Consolidated Edison Company of New York, Inc.
4 Irving Place
New York, New York 10003

Texas Power & Light
Fidelity Union Life Bldg.
P.O. Box 6331
Dallas, Texas 75222

Duke Power Company
(Hill-Power Supply Co.)
P.O. Box 1339
Charlotte, North Carolina 28201

Monongahela Power Company
1310 Fair Mount Avenue
Fairmont, West Virginia 26555

Ohio Edison Company
47 North Main Street
Akron, Ohio 44308

Wisconsin Electric Power Company
231 West Michigan Street
Milwaukee, Wisconsin 53201

Albert W. Hartman
Hartman Electric Manufacturing Co.
Hansfield, Ohio 44907

Wisconsin Power & Light
P.O. Box 192
Madison, Wisconsin