http://www.tukkaeit.com/showthread.php?t=2491&p=3605&viewfull=1#post3605



http://www.applej4ck.com/2011/02/06/how-to-untethered-jailbreak-ios-4-2-1-with-greenpois0n-windows/

http://www.flashfly.net/forums/index.php?sid=9a8120af4ff4694e4ee469ae5c730943




http://www.flashfly.net/forums/viewtopic.php?f=117&t=352147
http://www.jokergameth.com/board/showthread.php?p=2002365#post2002365
http://www.jokergameth.com/board/showthread.php?t=182499