Railroad Archives Online
- FondoD0011 - James M. Fredrickson Collection
- Serie004 - Northern Pacific Railroad Company
- Subserie014 - Photographs
- 003 - Railroad Buildings and Structures
- 004 - Maintenance of Way Support
- Unidad documental simpleJMF04-02772.0 - Northern Pacific section house at Martin, Washington, circa 1948.
- Unidad documental simpleJMF04-02810.0 - Northern Pacific section house and workers at Easton, Washington Territory, in 1887.
- Unidad documental simpleJMF04-02820.0 - Northern Pacific section house at Canyon Spur, Washington Territory, 1887.
- Unidad documental simpleJMF04-02828.0 - Northern Pacific engineering offices on Stampede Pass, Washington Territory, 1887.
- Unidad documental simpleJMF04-03161.0 - Northern Pacific section house at Frances, Washington, circa 1915.