Hemion, Geoffrey. 1988. “A discrete geometry: Speculations on a new framework for classical electrodynamics”. International Journal of Theoretical Physics 27 (10): 1145-1255.
Hemion, Geoffrey. 1979. “On the classification of homeomorphisms of 2-manifolds and the classification of 3-manifolds”. Acta Mathematica 142 (1): 119-155.