Railroad Archives Online
- FondiE0437 - Jim Parker Collection
- Serija004 - Northern Pacific Railroad Company
- Podserija014 - Photographs
- 001 - Railroads--Equipment and Supplies
- 006 - Cabooses (Railroads)
- Dokument48076 - Northern Pacific Caboose Number 1015 and Northern Pacific Freight Car 15593, Ellensburg, Washington, 1967
- Dokument48077 - Northern Pacific Caboose Number 1119, Sprague, Washington, 1967
- Dokument48078 - Northern Pacific Caboose Number 1398, Saint Cloud, Minnesota, 1967