Railroad Archives Online
- CollectionD0036 - George Werkema Collection
- Series004 - Northern Pacific Railroad Company
- Subseries Level 1014 - Photographs
- Subseries Level 2001 - Railroads--Equipment and Supplies
- Subseries Level 3002 - Diesel Locomotives
- 15 more...
- ItemWerkema034 - Northern Pacific 525 in Pasco, Washington, in 1968.
- ItemWerkema035 - Northern Pacific 555 in Seattle, Washington, in 1962.
- ItemWerkema036 - Northern Pacific 602 in Seattle, Washington, in 1961.
- ItemWerkema037 - Northern Pacific 700 at Fargo, North Dakota, in 1965.
- ItemWerkema038 - Northern Pacific 709 in Duluth, Minnesota, in 1968.
- ItemWerkema039 - Northern Pacific 750 in Duluth, Minnesota, in 1968.
- ItemWerkema040 - Northern Pacific 803 in Duluth, Minnesota, in 1962.
- ItemWerkema041 - Northern Pacific 858 in Minneapolis, Minnesota, in 1968.
- ItemWerkema042 - Northern Pacific 861 in Duluth, Minnesota, in 1969.
- 31 more...