Debiprasad Ghatak, Krishan Kumar Tyagi, and Eshna Tiwari. 2017. “Implant Placement in Posterior Atrophic Maxilla Using Direct and Indirect Sinus Augmentation- a Comparative Study”. Asian Pacific Journal of Health Sciences 4 (1):201-16. https://doi.org/10.21276/apjhs.2017.4.1.32.