1. Baum, G. Present status of orbital ultrasonography. Am. J. Ophthalmol. 56: 98 (1963).
2. Baum, G. A reappraisal of orbital ultrasonography: Series II. Trans. Am. Acad. Ophthalmol. Otolaryngol. 69: 943 (1965).
3. Acta fac. med. univ. brunensis;W Buschmann,1968
4. Buschmann, W. & Staudt, J. Grundlagen der echographischen differential Diagnostik. In: Ultrasonographia medica, Vol. 1 (J. Böck & K. Ossoinig, eds) Wien: Verl. Wiener med. Akad. (1971) p. 395.
5. Coleman, J., Lizzi, F. & Jack, R. Ultrasonography of the Eye and Orbit. Philadelphia: Lea & Febiger (1977)p. 296.