non-orientable

These are the finest closed, non-orientable, boundary-free manifolds sold anywhere in our three spatial dimensions.

hughstimson.org » Blog Archive » Monetizing the Klein Bottle 2008

It has the mathematical property of being non-orientable.

Totally One-sided 2008

It has the mathematical property of being non-orientable.

Yisrael Medad can’t take a joke, Wonkette misses the high-road | Jewschool 2007

The ones with even number of twists are orientable with two circular edges with varying linking number, and the odd-numbered twists are non-orientable with a single circular edge that links (knots) itself a varying number of times.

Boing Boing: July 25, 2004 - July 31, 2004 Archives 2004

Acme Klein Bottle - Nice site for "the finest closed, non-orientable, boundary-free manifolds sold anywhere in oõr three spatial dimensions."

Archive 2002-04-01 Ray Girvan 2002

Acme Klein Bottle - Nice site for "the finest closed, non-orientable, boundary-free manifolds sold anywhere in oõr three spatial dimensions."

Pattern, mathematics & games Ray Girvan 2002

All combat should occur on non-orientable surfaces.

D / RPG News the Jester 2010