We first heard the expletive version (which I am almost certain was the Chubby Brown version) in Germany where it was very, very popular and sung very loudly nightly in our chosen bar. It was quite funny to see some very demure young ladies joining in the "Who the...." lines with no embarrassment at all.

When the Germans made the return trip to visit us, they had to be taken to one side and encouraged not to sing it so loudly in our chosen English bar.

Weasel.