1. Phyllis A. Balch. Stress. In: a member of Penguin Group (USA) Inc. Prescription for Nutritional Healing. Forth Edition. New York: AVERY; 2006. p. 65-66.
1.https://www.webmd.com/vitamins-supplements/ingredientmono-202-bilberry.aspx?activeingredientid=202&
2.http://www.pfaf.org/USER/Plant.aspx?LatinName=Vaccinium+myrtillu
3.https://www.ncbi.nlm.nih.gov/books/NBK92770/figure/ch4_f4.1/?report=objectonly
4.https://www.webmd.com/eye-health/night-vision-problems-halos-blurred-vision-night-blindness#1
5.https://www.ncbi.nlm.nih.gov/pubmed/16075680
6. https://www.ncbi.nlm.nih.gov/books/NBK92770/
7. https://www.ncbi.nlm.nih.gov/books/NBK92770/#
8. https://www.ncbi.nlm.nih.gov/books/NBK92770/
9.https://www.ncbi.nlm.nih.gov/pubmed/24080533
10.www.nlm.nih.gov/medlineplus/druginfo/natural/202.html
