Railroad Archives Online
- FondD0046 - Andrew Klamka Collection
- Sorozat003 - Great Northern Railway Company (U.S.)
- Alsorozat004 - Library
- 002 - Periodicals
- 1%% több...
- IratdarabGNSemaphoreVol3No1 - 'Great Northern Semaphore' January 1926
- IratdarabGNSemaphoreVol3No2 - 'Great Northern Semaphore' February 1926
- IratdarabGNSemaphoreVol3No3 - 'Great Northern Semaphore' March 1926
- IratdarabGNSemaphoreVol3No4 - 'Great Northern Semaphore' April 1926
- IratdarabGNSemaphoreVol3No5 - 'Great Northern Semaphore' May 1926
- IratdarabGNSemaphoreVol3No6 - 'Great Northern Semaphore' June 1926
- IratdarabGNSemaphoreVol3No7 - 'Great Northern Semaphore' July 1926
- IratdarabGNSemaphoreVol3No8 - 'Great Northern Semaphore' August 1926
- IratdarabGNSemaphoreVol3No9 - 'Great Northern Semaphore' September 1926
- 1%% több...