Railroad Archives Online
- FondsD0063 - Walter W. Ainsworth Collection
- Cyfres004 - Northern Pacific Railroad Company
- Is-gyfres014 - Photographs
- 001 - Railroads--Equipment and Supplies
- 011 - Railroad cars self-propelled
- EitemWWANT019 - Northern Pacific gas electric motor car B-19 at Seattle, Washington, in 1938.
- EitemWWANT054 - Northern Pacific gas electric motor car B-19 at Seattle, Washington, in 1939.
- EitemWWANT083 - Northern Pacific gas electric motor car B-18 at Black River, Washington, circa 1935.
- EitemWWANT108 - Northern Pacific gas electric motor car B-18 at South Bend, Washington, in 1929.