1. Dodd, G.D. and Jing, B-S:Radiology of the nose, paranasal sinuses, and nasopharynx. 1st ed. pp. 215–261, 1977, Williams & Wilkins, Baltimore
2. Lloyd, G.A.S.: Diagnostic imaging of the nose and paranasal sinuses.J. Laryngol. Otol. 103: 453–461, 1989
3. Valvassori, G.E., Buckingham, R.A., Carter, B.L., Hanafee, W.N. and Mafee, M.F.:Head and neck imaging, 1st ed. pp. 182–191, 1988, Igaku Shoin Ltd., Tokyo
4. Hirakawa, K., Sugimoto, Y., Yajin, K. and Kikuya, Y.: Statistical observations on cases with unilateral shadow of maxillary sinus.Pract. Otol. Kyoto. 74: 2111–2117, 1981 (in Japanese)
5. Ohhira, S., Ariga, H., Ishida, M., Yane, K. and Hyo, Y.: CT images of unilateral sinus lesions.J. Otolaryngol. Jpn. 88: 1040–1044, 1985 (in Japanese)