Nasr, S., D. E. Slot, S. Bahaa, C. E. Dorfer, and K. F. M. El-Sayed,
"Dental implants combined with sinus augmentation: What is the merit of bone grafting? A systematic review",
Journal of Cranio-Maxillo-Facial Surgery, vol. 44, issue 10, pp. 1607-1617, 2016.