The Princeton University Digital Collection has a nice collection of early IRT Subway Sun and Elevated Express posters.
http://diglib.princeton.edu/xquery?_xq= ... 085-ivylee
[BTW - I knew about the Subway Sun but had never heard of the Elevated Express until I saw them today on the above site.]
http://diglib.princeton.edu/xquery?_xq= ... 085-ivylee
[BTW - I knew about the Subway Sun but had never heard of the Elevated Express until I saw them today on the above site.]