Origami - 6 un - Retângulo Impossível - Magic Rings - Umulius Rectangulum - Thoki Yenn

Fonte:

http://www.britishorigami.info/academic/thok/umulius.html

http://www.britishorigami.info/academic/thok/billumu.html

http://www.flickr.com/photos/malachus/3982559442/
http://www.flickr.com/photos/olivier_c/3097924473/