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 3003 - Freight Cars
- 202 more...
- ItemWerkema333 - Northern Pacific hopper car number 76561 at Amarillo, Texas, in 1980.
- ItemWerkema334 - Northern Pacific hopper car number 76717 at Amarillo, Texas, in 1979.
- ItemWerkema335 - Northern Pacific hopper car number 76717 at Amarillo, Texas, in 1979.
- ItemWerkema336 - Northern Pacific hopper car number 76737 at Albuquerque, New Mexico, in 1979.
- ItemWerkema337 - Northern Pacific hopper car number 76764 at Pasco, Washington, in 1983.
- ItemWerkema338 - Northern Pacific hopper car number 76769 at Amarillo, Texas, in 1980.
- ItemWerkema339 - Northern Pacific hopper car number 76800 at Amarillo, Texas, in 1980.
- ItemWerkema340 - Northern Pacific hopper car number 76820 at Pasco, Washington, in 1981.
- ItemWerkema341 - Northern Pacific hopper car number 76864 at Albuquerque, New Mexico, in 1978.
- 12 more...