Primary:
https://www.gilderlehrman.org/history-by-era/civil-rights-movement/essays/importance-muhammad-ali
http://digital.wustl.edu/e/eii/eiiweb/ali5427.0743.004marc_record_interviewer_process.html
Internet sites:
http://www.biography.com/people/muhammad-ali-9181165#boxing-comeback
http://www.history.com/topics/black-history/muhammad-ali
Books:
Muhammad Ali, The Greatest: My Own Story by Richard Durham
Ali, Muhammad 1942- by Ed. Judith S. Baughman, Victor Bondi, Richard Layman, Tandy McConnell, and Vincent Tompkins.
Magazine:
http://www.mensjournal.com/magazine/how-muhammad-ali-conquered-fear-and-changed-the-world-20130205
