References
http://www.vatican.va/archive/ENG0015/__P86.HTM
http://wayback.archive.org/web/20081221212759/http://www.vatican.va/archive/catechism/p3s2c2a6.htm
http://www.ewtn.com/faith/teachings/index.asp
http://catholicreligionteacher.com/
http://www.infoplease.com/encyclopedia/society/roman-catholic-church-beliefs-doctrines-practices.html
http://wayback.archive.org/web/20081221212759/http://www.vatican.va/archive/catechism/p3s2c2a6.htm
http://www.ewtn.com/faith/teachings/index.asp
http://catholicreligionteacher.com/
http://www.infoplease.com/encyclopedia/society/roman-catholic-church-beliefs-doctrines-practices.html