Published online by Cambridge University Press: 22 February 2012
Cromwell and Marar present an analysis of semi-regular (generic) surfaces with a single triple point and connected self-intersection set. Six of their surfaces are the projective plane, including Boy's surface and Steiner's surface. We build on their work by incorporating twists similar to that of Apery's immersion of the projective plane and show that with a few additional surfaces, all such generic maps of the projective plane are now identified.