Other
Barnum Museum
This website gives information on P.T. Barnum himself and special exhibits like Jumbo, the African elephant, and Tom Thumb.
Smithsonian Institution
Nat'l Portrait Gallery: Ballyhoo! Posters as Portraiture: Greatest Show on Earth
See a poster advertising The Greatest Show on Earth and read text explaining why the poster was so important to advertising the circus.
Curated OER
Educational Technology Clearinghouse: Clip Art Etc: Phineas T. Barnum
(1810-1891) Entertainer that teamed up with Bailey to start the Barnum and Bailey circus.