Alles over burrs
Alles over burrs
http://www.research.ibm.com/burrpuzzles/index.html
Oplossingen
Oplossingen
http://burrtools.sourceforge.net/
Trevor Wood
Puzzles. a gallery of individually hand crafted mechanical puzzles made from fine and exotic woods by trevor wood (t.w. puzzles) for the discerning collector.
http://www.puzzles.force9.co.uk/