Railroad Archives Online
- CollectionD0063 - Walter W. Ainsworth Collection
- Series003 - Great Northern Railway Company (U.S.)
- Subseries Level 1014 - Photographs
- Subseries Level 2003 - Railroads--Buildings and Structures
- Subseries Level 3001 - Bridges
- Subseries Level 3002 - Depots and Freighthouses
- Subseries Level 3007 - Tunnels
- Subseries Level 3010 - Miscellaneous Structures