Sikalo, Yu. K., and M. A. Stanislavchuk. “Correlation of Melatonin and TNF-α Levels With Characteristics of Sleep in Patients With Rheumatoid Arthritis”. Zaporozhye Medical Journal 17, no. 1 (February 9, 2015). Accessed May 2, 2024. http://zmj.zsmu.edu.ua/article/view/39213.