Nandha, R., and M. K. Chhabra. “Prevalence and Clinical Characteristics of Headache in Dental Students of a Tertiary Care Teaching Dental Hospital in Northern India”. International Journal of Basic & Clinical Pharmacology, vol. 2, no. 1, Jan. 2017, pp. 51-55, https://www.ijbcp.com/index.php/ijbcp/article/view/1211.