Railroad Archives Online
- FondsD0027 - Timothy Miller Collection
- Série003 - Great Northern Railway Company (U.S.)
- Sous-série009 - Engineering Records
- 008 - Physical plant drawing
- 008 - Tunnels
- 340 en plus...
- PièceStruc004569 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- PièceStruc004570 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- PièceStruc004571 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- PièceStruc004572 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- PièceStruc004573 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- PièceStruc004574 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- PièceStruc004575 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- PièceStruc004576 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1971
- PièceStruc004577 - Great Northern Engineering Drawing, Flathead Tunnel, Montana, 1975
- 3 en plus...