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
- 22 more...
- ItemWerkema041 - Northern Pacific 858 in Minneapolis, Minnesota, in 1968.
- ItemWerkema042 - Northern Pacific 861 in Duluth, Minnesota, in 1969.
- ItemWerkema043 - Northern Pacific 910 in Minneapolis, Minnesota, in 1968.
- ItemWerkema044 - Northern Pacific 915 and 6019A at Livingston, Montana, in 1965.
- ItemWerkema045 - Northern Pacific 2500 at Livingston, Montana, in 1965.
- ItemWerkema046 - Northern Pacific 2514 and 2500 at Livingston, Montana, in 1965.
- ItemWerkema047 - Northern Pacific 2807 in Minneapolis, Minnesota, in 1968.
- ItemWerkema048 - Northern Pacific 3304 in Pasco, Washington, in 1968.
- ItemWerkema049 - Northern Pacific 3600 in Minneapolis, Minnesota, in 1968.
- 24 more...