Need help to solve a football question

[Edge]

Man Utd, Liverpool, Charlton, Oldham, Villa & Leeds have done it. Villa done it first attempt, Liverpool done it in a peculiar way, Wimbledon can’t do it unless Palace go bankrupt & Arsenal can’t do it unless they sack Wenger.

What is it?

[Anonymous]

Oh i've heard this one before and forgot the answer...We spent a whole afternoon at work one day trying to find it out

[Anonymous]

Found it!
have a look here (scroll down a fair bit)
http://football.guardian.co.uk/news/theknowledge/0,9204,650310,00.html