1. On moore graphs with diameters 2 and 3;Hoffman;IBM J. Res. Develop.,1960
2. A further characterization of geodetic graphs;Stemple,1966
3. On planar geodetic graphs;Stemple;J. Combinatorial Theory,1968
4. A characterization of the planar geodetic graph and some geodetic properties of nonplanar graphs;Watkins,1964