1. A New Theory of Human Evolution;Keith,1949
2. The Adaptive Chin, Springfield, Ill.;DuBrul,1954
3. Variations in Facial Relationships: Their Significance in Treatment and Prognosis;Downs;Am. J. Orthodontics,1948
4. Björk, A.: The Face in Profile, Lund, Berlingska Boktryckeriet.
5. Muskelmarken am Schadel;Virchow;Itsder. Ethnol.,1910