The 1939 New York World's Fair song "Dawn of a New Day" was written by George and Ira Gershwin. Unfortunately, I don't remember where I found the song so I can't give credit where credit is due. You can listen to the song here.
Railroads on Parade (1939)
All's Fair at the Fair (1938)
Memory of 'Tomorrow' (New York Times, 1941)
Donald Duck's "Modern Inventions" (1937)
Metal Man Comes to Life (1939)