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
- 198 more...
- ItemWerkema329 - Northern Pacific hopper car number 76481 at Plainview, Texas, in 1985.
- ItemWerkema330 - Northern Pacific hopper car number 76482 at Albuquerque, New Mexico, in 1980.
- ItemWerkema331 - Northern Pacific hopper car number 76502 at Amarillo, Texas, in 1980.
- ItemWerkema332 - Northern Pacific hopper car number 76502 at Amarillo, Texas, in 1980.
- 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.
- 16 more...