V.Rajkumar1 , Mrs. J.Nithyashri2. “Identifying the Human Age Group Using Active Appearance Model and KNN Classifier”. International Journal of Emerging Trends in Science and Technology, Vol. 3, no. 06, June 2016, pp. 4157-62, https://igmpublication.org/ijetst.in/index.php/ijetst/article/view/1122.