D. Salman, . F. ., R. . .J Al-Naimi, and K. . M. Saleh. “Prevalence and Severity of Root Caries in Qat Chewing in Yemen (Thamar)”. Mustansiria Dental Journal, vol. 1, no. 2, Dec. 2004, pp. 197-01, doi:10.32828/mdj.v1i2.1107.