C. Paul Bonnington Atsuhiro Nakamoto Geometric Realization of a Triangulation on the Projective Plane with One Face Removed. 141-157 2008 40 Discrete & Computational Geometry 1 http://dx.doi.org/10.1007/s00454-007-9035-9 db/journals/dcg/dcg40.html#BonningtonN08