1. Vorlesungen über Geometrie der Algebren;Benz,1973
2. Geometric and pseudo-geometric graphs (q2+1,q+1,q);Bose;J. Geom.,1973
3. Dimensional linear spaces;Delandtsheer,1995
4. Einführung in die Kombinatorik;Halder,1976
5. Finite Projective Spaces of Three Dimensions;Hirschfeld,1985