Railroad Archives Online
- CollectionE0483 - Great Northern Railway Historical Society Standard Signal Plans Collection
- Series003 - Great Northern Railway Company (U.S.)
- Subseries Level 1009 - Engineering Records
- Subseries Level 2008 - Physical plant drawing
- Subseries Level 3005 - Signals
- 103 more...
- Item167-129 - Great Northern Railway Standard Signal Plans; Cable, Dead Ends and Hangers, 1962
- Item167-131 - Great Northern Railway Standard Signal Plans; Cover, Station Indicator, 1923
- Item167-132 - Great Northern Railway Standard Signal Plans; Indicator, Station, 1923
- Item167-133 - Great Northern Railway Standard Signal Plans; Base for 4 Inch Mast, 1923
- Item167-134A - Great Northern Railway Standard Signal Plans; Bonding, Wireing, for Switches and Crossovers, 1928
- Item167-135 - Great Northern Railway Standard Signal Plans; Studs and Special Nuts for Raising Signals and Cable Posts, 1923
- Item167-138 - Great Northern Railway Standard Signal Plans; Bracket Number Plate, 1924
- Item167-139B - Great Northern Railway Standard Signal Plans; Bracket, Horn, 1925
- Item167-140 - Great Northern Railway Standard Signal Plans; Markers, Permissive and Stop Signal, 1929
- 16 more...