Railroad Archives Online
- CollectionD0063 - Walter W. Ainsworth Collection
- Series001 - Burlington Northern Railroad Company
- Subseries Level 1014 - Photographs
- Subseries Level 2003 - Railroads--Buildings and Structures
- Subseries Level 3001 - Bridges
- ItemWWAPC0411 - Former Burlington Northern Railroad/Chicago Milwaukee St. Paul and Pacific ailroad bridge near Renton, Washington, circa 1990.
- ItemWWAPC0670 - Former Burlington Northern Railroad bridge at Elliott, Washington, circa 1985.
- ItemWWAPC0714 - Burlington Northern Railroad trestle bridge at Maple Valley, Washington, circa 1971.
- ItemWWAPC0715 - Burlington Northern Railroad trestle bridge at Maple Valley, Washington, circa 1971.