Sources:
- http://www.english-online.at/history/1960s/society-and-change-in-the-sixties.htm
- http://www.history.com/topics/1960s
- http://www.pbs.org/opb/thesixties/timeline/timeline_text.html
- http://www.bbhq.com/thennnow.htm
- http://www.urbanadventures.com/blog/hippies-guide-san-francisco.html