Al-Ubaydi, Ammar Sh, and Nagham M J Al- Mothaffar. 2013. “Evaluation of Andrews’ Six Keys of Normal Occlusion in a Sample of Iraqi Adults in Baghdad City”. Journal of Baghdad College of Dentistry 25 (2): 130-39. https://jbcd.uobaghdad.edu.iq/index.php/jbcd/article/view/241.