Railroad Archives Online
- CollectionE0357 - Wade J Stevenson Collection
- Series005 - Pacific Coast Railroad Company
- Subseries Level 1014 - Photographs
- Subseries Level 2001 - Railroads--Equipment and Supplies
- Subseries Level 3006 - Cabooses (Railroads)
- ItemGNRHS.55.12.18 - Pacific Coast Caboose X1 in Seattle, Washington, circa 1952
- ItemGNRHS.55.12.19 - Pacific Coast Caboose X1 in Seattle, Washington, circa 1952
- ItemGNRHS.55.12.20 - Pacific Coast Caboose X1 in Seattle, Washington, circa 1952
- ItemGNRHS.55.14.22 - Pacific Coast Caboose X1 in Renton, Washington, undated
- ItemGNRHS.55.15.03 - Pacific Coast Caboose X1 in Seattle, Washington, circa 1952
- ItemGNRHS.55.15.04 - Pacific Coast Caboose X1 in Seattle, Washington, circa 1952
- ItemGNRHS.55.15.06 - Pacific Coast Caboose X1 in Seattle, Washington, circa 1952
- ItemGNRHS.55.15.07 - Pacific Coast Caboose X1 in Seattle, Washington, circa 1952