TIME 100: Scientists and Thinkers - Edwin Hubble
A short history of the man and his work.
http://www.time.com/time/time100/scientist/profile/hubble.html

Ewin Hubble
Detail of his work and theories, with a list of references.
http://antwrp.gsfc.nasa.gov/diamond_jubilee/1996/sandage_hubble.html