1. Arnold, W. & Ganzer, U. (1980): Seromuco-tympanum and bone conduction: Proposed new classification of ear diseases caused by Eustachian tube dysfunction. In physiology of Eustachian tube and Middle ear (International Symposium, Freiburg, 1977) pp 71–78 p. 194 Georg Thieme verlag.
2. Citron, L., Dix, M., Hallpike, C., and Hood, J. (1963): A recent Clinico-pathological study of Cochlear nerve degeneration resulting from tumor pressure and disseminated sclerosis, with particular reference to the finding of normal threshold sensitivity for pure tones.Acta Otolaryngologica (Stockholm) 56, 330–337- as quoted by D. Plester.
3. D. Plester- (1982): Fluctuant hearing loss. Otology-Edited by Alan G. Gibb and Mansfield F. W. Smith. Published by Butterwroths, International Medical Reviews-London-216–225.
4. Huizing, E. H. (1964): As quoted by D. Plester.
5. Jahnke, K. (1977): As quoted by D. Plester.