S. M. Rayegani, M. H. Bahrami, D. Elyaspour, M. Saeidi, and H. Sanjari, “Therapeutic Effects of Low Level Laser Therapy (LLLT) in Knee Osteoarthritis, Compared to Therapeutic Ultrasound”, J laser Med Sci, vol. 3, no. 2, pp. 71–74, May 2012.