Railroad Archives Online
- CollectionD0046 - Andrew Klamka Collection
- Series003 - Great Northern Railway Company (U.S.)
- Subseries Level 1004 - Library
- Subseries Level 2002 - Periodicals
- 55 more...
- ItemGNSemaphoreVol5No8 - 'Great Northern Semaphore' August 1928
- ItemGNSemaphoreVol5No9 - 'Great Northern Semaphore' September 1928
- ItemGNSemaphoreVol5No10 - 'Great Northern Semaphore' October 1928
- ItemGNSemaphoreVol5No11 - 'Great Northern Semaphore' November 1928
- ItemGNSemaphoreVol5No12 - 'Great Northern Semaphore' December 1928