G'day,

I'm not too sure of the import of JohnInKansas's:
"... but just for those interested in "sourcing" ...A Book of Vulgar Verse, by A Gentleman About Town, Checker Books, Toronto, 1981, ..." -
however, the version alluded to above by JennieG was collected in Lithgow, New South Wales, Australia by John Meredith in 1954.

As it went to the tune (and used the "Knock, knock, knock" device) of the novelty pop song The Thing, that particular version would seem to have been fairly new at that time.

Regards,

Bob Bolton