Maxillary Sinoscopic View of the “Infraostial Ridge” for Identification of the Natural Ostium of the Maxillary Sinus

Hollinshead WH . Anatomy for Surgeons. Vol. 1-Head and Neck. 2^nd ed. New York: Harper & Row, 1968:296–8.

Draf W. Endoscopy of the Paranasal Sinuses-Technique, Typical Findings, Therapeutic Possibilities. Translated by Pohl WE . Berlin, Germany: Springer-Verlag, 1983:33–5, 72-5.