Wahid, Abdul, and Sajjad Ahmad. “CARCINOMA OF ORAL CAVITY AND OROPHARYNX IN SMOKELESS TOBACCO USERS OF ALL AGE GROUPS”. Journal of Ayub Medical College Abbottabad, vol. 10, no. 2, May 1998, pp. 21-22, https://jamc.ayubmed.edu.pk/index.php/jamc/article/view/4818.