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 3006 - Cabooses (Railroads)
- 7 more...
- ItemWerkema365 - Northern Pacific wood caboose 1314 at Sumas, Washington, in 1968.
- ItemWerkema366 - Northern Pacific wood caboose 1314 at Sumas, Washington, in 1968.
- ItemWerkema367 - Northern Pacific wood caboose 1314 at Sumas, Washington, in 1968.
- ItemWerkema368 - Burlington Northern wood caboose 10943 at Kansas City, Missouri, in 1975.
- ItemWerkema369 - Northern Pacific wood caboose 1740 at Boone, Iowa, in 1993.
- ItemWerkema370 - A Northern Pacific wood caboose at Vancouver, Washington, in 2001.