Railroad Archives Online
- CollectionD0036 - George Werkema Collection
- Series003 - Great Northern Railway Company (U.S.)
- Subseries Level 1014 - Photographs
- Subseries Level 2003 - Railroads--Buildings and Structures
- Subseries Level 3005 - Signals
- 18 more...
- Itemimg1209 - Great Northern Sign at Odessa, Washington, 1987
- Itemimg1210 - Great Northern Sign at Stratford, Washington, 1987
- Itemimg1211 - Great Northern Sign at Stratford, Washington, 1987
- Itemimg1212 - Great Northern Sign at Sultan, Washington, 1987
- Itemimg1213 - Great Northern Sign at Wilson Creek, Washington, 1987