sources

Batman

http://www.superherostuff.com/biographies/batman_biography.html
http://www.dcuguide.com/who.php?name=BATMAN
http://www.comicvine.com/batman/4005-1699/
http://www.nickwalden.com/.../batman_-_history_of_dark_knight_7-03.doc%E2%80%8E

Captain America
http://en.wikipedia.org/wiki/Captain_America
http://www.comicvine.com/captain-america/4005-1442/
http://marvel.com/universe/Captain_America_(Steve_Rogers)

Doctor Doom
http://comics.ign.com/top-100-villains/3.html
http://en.wikipedia.org/wiki/Doctor_Doom
http://www.comicvine.com/doctor-doom/4005-1468/

Green Arrow
http://www.comicvine.com/green-arrow/4005-5936/
http://dc.wikia.com/wiki/Green_Arrow_(Oliver_Queen)
http://dc.wikia.com/wiki/Roy_Harper_(New_Earth)

The Joker
http://www.dcuwiki.net/w/Joker 
http://batman.wikia.com/wiki/The_Joker 

Majin Boo
http://dragonball.wikia.com/wiki/Majin_Buu
http://www.comicvine.com/buu/4005-41116/

Magneto 
http://www.comicvine.com/magneto/4005-1441/
http://marvel.wikia.com/Max_Eisenhardt_(Earth-616)

Superman
 http://en.wikipedia.org/wiki/Origin_of_Superman
http://dc.wikia.com/wiki/Superman_Origins
http://www.angelfire.com/comics/superman_void/index2.html
http://theages.ac/origin/