1. Graph Theory with Applications;Bondy,1976
2. Integral distance graphs;Chang,1995
3. Unsolved Problems in Geometry;Croft,1991
4. New results on 3-chromatic prime distance graphs;Eggleton;Ars Combin.,1988
5. Colouring the real line;Eggleton;J. Combin. Theory Ser. B,1985