1. Cranio-facial morphology in congenital clefts of the lip and palate;Dahl;Acta Odontol. Scand.,1970
2. Inheritance of harelip and cleft palate;Fogh-Andersen;Nyt Nordisk Forlag, Copenhagen,1942
3. A classification of cleft lip and palate;Harkins;Plastic Reconstruct. Surg.,1962
4. A new classification for cleft lip and palate;Kernahan;Plastic Reconstruct. Surg.,1958
5. Classification of clefting;Veau,1938