Puthukudy, P.A., Feshan, M. and Karuthedath, S. 2022. A 3 years retrospective observational study of pure tone audiometry in a tertiary railway hospital. International Journal of Otorhinolaryngology and Head and Neck Surgery. 8, 4 (Mar. 2022), 348–355. DOI:https://doi.org/10.18203/issn.2454-5929.ijohns20220802.