Norkus, S., and S. . Ryan. “THE EFFECT OF SPINAL MANIPULATION AS COMPLEMENTARY THERAPY FOR PARKINSON’S DISEASE SYMPTOMATOLOGY: A LITERATURE REVIEW”. Journal of Contemporary Chiropractic, vol. 3, no. 1, Jan. 2020, pp. 7-13, https://journal.parker.edu/index.php/jcc/article/view/91.