1. Benz M, Laboureux X, Maier T, Nkenke E, Seeger S, Neukam FW, Häusler G: The symmetry of faces. In: Greiner G, Niemann H, Ertl T, Girod B, Seidel HP (eds.). Vision, Modeling, and Visualization. Amsterdam: IOS Press, 2002; 332–339
2. Buschmann W, Schwaar R: On exophthalmometry. I. The relationship between center of the globe and orbital rim. Albrecht Von Graefes Arch Klin Exp Ophthalmol 173: 261–268, 1967
3. Cole HP, Couvillion JT, Fink AJ, Haik BG, Kastl PR: Exophthalmometry: a comparative study of the Naugle and Hertel instruments. Ophthalmic Plast Reconstr Surg 13: 189–194, 1992
4. Davanger M: Principles, sources of error in exophthalmometry. Acta Ophthalmol 48: 625–633, 1970
5. Dolynchuk KN, Tadjalli HE, Manson PN: Orbital volumetric analysis: clinical application in orbitozygomatic complex injuries. J Cranio-Maxillofac Trauma 2: 56–63, 1996