The International Rules of Underwater Hockey

WAA Rules Volume 1 - Tournament Regulations and Playing Area Requirements - Version 1.3 March 2009.
WAA Rules Volume 2 - Rules of Play - Version 1.3 March 2009.
WAA Referee Manual Level 1 - Version 8.12 November 2003. This document is based on the work of Graham Henderson and is very useful for improving knowledge of the Rules.