Menon Ravunniarth, L., and G. K. Narayana. “Nasal Endoscopic Evaluation of Patients Presenting With Frontal Headache”. International Journal of Otorhinolaryngology and Head and Neck Surgery, vol. 6, no. 1, Dec. 2019, pp. 137-42, doi:10.18203/issn.2454-5929.ijohns20195704.