Bum trilogy

The Bum Trilogy consists of three books by Australian author Andy Griffiths. They are aimed at children aged around 10 and contain lots of toilet humor.

In the United States, the word "bum" has another meaning (i.e. homeless vagrant), so it is changed to "butt" in the versions sold there. The third book is further renamed to Butt Wars: The Final Conflict.

Griffiths' reference guide to "prehistoric bumosaurs", What Bumosaur Is That?, was published in May 2007. It is not a part of the trilogy, although the book was mentioned in the trilogy.

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