Referencer:
Vitamin B12: Are You Getting It?
What Every Vegan Should Know about Vitamin B12
NutritionFacts.org (søg på vitamin B12)
What is the Role of Supplements in a Healthy Diet?
Journal of the Academy of Nutrition and Dietetics.
Position of the American Dietetic Association: Vegetarian Diets
July 2009 Volume 109, Issue 7, Pages 1266–1282
DOI: http://dx.doi.org/10.1016/j.jada.2009.05.027
http://www.vrg.org/nutrition/2009_ADA_position_paper.pdf
https://www.nap.edu/read/6015/chapter/11
