Railroad Archives Online
- FondsD0027 - Timothy Miller Collection
- Cyfres003 - Great Northern Railway Company (U.S.)
- Is-gyfres009 - Engineering Records
- 008 - Physical plant drawing
- 008 - Tunnels
- 267 mwy...
- EitemStruc004496 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1970
- EitemStruc004497 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- EitemStruc004498 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- EitemStruc004499 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- EitemStruc004500 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- EitemStruc004501 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- EitemStruc004502 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- EitemStruc004503 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- EitemStruc004504 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- 76 mwy...