In 1923, Union Pacific published a Yellowstone booklet with a painted cover similar to California Calls You and the 1923 Pacific Northwest booklet. I don’t have the Yellowstone version (which is pictured below the jump), but I do have a 1924 booklet that appears to be an early version of the embossed-cover booklets.
The text, UP logo, and Old Faithful image are all embossed on the cover, but there is no gilt printing and the cover’s color doesn’t seem to be keyed to any natural features in the park. The booklet explains that people wanting to go to the park can take Union Pacific’s “fast, through trains from Chicago” to Salt Lake City, where they can catch the Yellowstone Special, which goes overnight to West Yellowstone. Passengers to or from Portland can also catch the Yellowstone Express from Pocatello, arriving in West Yellowstone in the mid-afternoon.
Union Pacific’s 1923 Yellowstone booklet–not yet available as a download.