Railroad Archives Online
- CollectionD0063 - Walter W. Ainsworth Collection
- Series004 - Northern Pacific Railroad Company
- Subseries Level 1014 - Photographs
- Subseries Level 2001 - Railroads--Equipment and Supplies
- Subseries Level 3001 - Steam Locomotives
- 263 more...
- ItemWWANT300 - Northern Pacific steam locomotive number 4011 at Martin, Washington, circa 1925.
- ItemWWANT301 - Northern Pacific steam locomotive number 4014 at Easton, Washington, circa 1928.
- ItemWWANT302 - Northern Pacific steam locomotive number 4014 at Auburn, Washington, circa 1928.
- ItemWWANT303 - Northern Pacific steam locomotive number 4019 at Auburn, Washington, circa 1928.
- ItemWWANT304 - Northern Pacific steam locomotive number 4024 at Martin, Washington, circa 1925.