Because it appears that all of the brochure was not able to be viewed, a copyright search for renewals of pamphlets and periodicals for the years 1955 and 1956 was done for Union Pacific Railroad. There were no renewals listed for the railroad. While I believe the brochure was published without a copyright notice, I will license it as not renewed to be certain.
Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (70 years p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.
{{Information |Description=Brochure for the Union Pacific train "Portland Limited". The train was later replaced by The Portland Rose. |Source=[http://www.ebay.com/itm/UNION-PACIFIC-RR-1928-PORTLAND-LTD-NAME-TRAIN-FOLDER-/150914172520?pt=LH_DefaultDom...