1. Marrie RA, Horwitz RI. Emerging effects of comorbidities on multiple sclerosis. The Lancet Neurology. 2010; 9(8):820-8.
2. Kurtzke JF. Epidemiologic contributions to multiple sclerosis an overview. Neurology. 1980; 30(7 Part 2):61-79.
3. Eskandarieh S, Heydarpour P, Minagar A, Pourmand S, Sahraian MA. Multiple sclerosis epidemiology in East Asia, South East Asia and South Asia: a systematic review. Neuroepidemiology. 2016; 46(3):209-21.
4. Melcon MO, Correale J, Melcon CM. Is it time for a new global classification of multiple sclerosis? Journal of the neurological sciences. 2014; 344(1):171-81.
5. Khan F, Pallant J, Brand C. Caregiver strain and factors associated with caregiver self-efficacy and quality of life in a community cohort with multiple sclerosis. Disability and rehabilitation. 2007; 29(16):1241-50.
6. Younus Z, Vaughn CB, Sanai SA, Kavak KS, Gupta S, Nadeem M, et al. Fatigue and Mood States in Nursing Home and Nonambulatory Home-Based Patients with Multiple Sclerosis. International journal of MS care. 2017; 19(6):297-302.
7. Minden S, Frankel D, Hadden L, Perloff J, Srinath K, Hoaglin D. The Sonya Slifka longitudinal multiple sclerosis study: methods and sample characteristics. Multiple Sclerosis Journal. 2006; 12(1):24-38.
8. Rosti‐Otajärvi E, Hämäläinen P, Wiksten A, Hakkarainen T, Ruutiainen J. Validity and reliability of the Fatigue Severity Scale in Finnish multiple sclerosis patients. Brain and behavior. 2017;7(7): e00743.
9. Gilgun-Sherki Y, Melamed E, Offen D. The role of oxidative stress in the pathogenesis of multiple sclerosis: the need for effective antioxidant therapy. Journal of neurology. 2004; 251(3):261-8.
10. Haider L, Fischer MT, Frischer JM, Bauer J, Höftberger R, Botond G, et al. Oxidative damage in multiple sclerosis lesions. Brain. 2014; 344(1):171-81.
11. Reiter RJ, Tan D-X, Manchester L, Terron MP, Flores L, Koppisepi S. Medical implications of melatonin: receptor-mediated and receptor-independent actions. Advances in Medical Sciences (De Gruyter Open). 2007; 52.
12. Korkmaz A, Reiter RJ, Topal T, Manchester LC, Oter S, Tan D-X. Melatonin: an established antioxidant worthy of use in clinical trials. Molecular Medicine. 2009; 15(1-2):43.
13. Adamczyk-Sowa M, Sowa P, Pierzchala K, Polaniak R, Labuz-Roszak B. Antioxidative enzymes activity and malondialdehyde concentration during mitoxantrone therapy in multiple sclerosis patients. J Physiol Pharmacol. 2012; 63(6):683-90.
14. Tan DX, Manchester LC, Terron MP, Flores LJ, Reiter RJ. One molecule, many derivatives: A never‐ending interaction of melatonin with reactive oxygen and nitrogen species? Journal of pineal research. 2007; 42(1):28-42.
15. Tomás‐Zapico C, Coto‐Montes A. A proposed mechanism to explain the stimulatory effect of melatonin on antioxidative enzymes. Journal of pineal research. 2005; 39(2):99-104.
16. Adamczyk-Sowa M, Pierzchala K, Sowa P, Mucha S, Sadowska-Bartosz I, Adamczyk J, et al. Melatonin acts as antioxidant and improves sleep in MS patients. Neurochemical research. 2014; 39(8):1585-93.
17. Cullen O’Gorman RL, Bruce Taylor. Environmental Risk Factors for Multiple Sclerosis: A Review with a Focus on Molecular Mechanisms. Int J Mol Sci. 2012; 13:11718-52.
18. Jan Dörr SO, Horst Skarabis, Friedemann Paul. Efficacy of Vitamin D Supplementation in Multiple Sclerosis (EVIDIMS Trial): study protocol for a randomized controlled trial. Trials. 2012; 13(15):1-6.
19. Braley TJ, Chervin RD. Fatigue in multiple sclerosis: mechanisms, evaluation, and treatment. Sleep. 2010; 33(8):1061-7.
20. Shahvaroughi-Farahani Az, A'zimiyan M, Fallah-Pour M, Karimlou M. Fatigue Severity Scale (FSS): Evaluation of Reliability of the Persian Version among Persons with Multiple Sclerosis. Journal of Rehabilitation. 2010; 10(4):0-.
21. Thompson AJ, Banwell BL, Barkhof F, Carroll WM, Coetzee T, Comi G, et al. Diagnosis of multiple sclerosis: 2017 revisions of the McDonald criteria. The Lancet Neurology. 2017.
22. Farhadi N, Oryan S, Nabiuni M. Serum levels of melatonin and cytokines in multiple sclerosis. Biomedical journal. 2014; 37(2):90.
23. Adamczyk-Sowa M, Pierzchala K, Sowa P, Polaniak R, Kukla M, Hartel M. Influence of melatonin supplementation on serum antioxidative properties and impact of the quality of life in multiple sclerosis patients. J Physiol Pharmacol. 2014; 65(4):543-50.
24. Adamczyk-Sowa M, Pierzchala K, Sowa P, Mucha S, Sadowska-Bartosz I, Adamczyk J, et al. Melatonin acts as antioxidant and improves sleep in MS patients. Neurochemical research. 2014; 39(8):1585-93.
25. Melamud L, Golan D, Luboshitzky R, Lavi I, Miller A. Melatonin dysregulation, sleep disturbances and fatigue in multiple sclerosis. Journal of the neurological sciences. 2012; 314(1-2):37-40.