Cobalmin (Vitamin B12) Dietary Supplement Fact Sheet: Vitamin B12 DHHS. NIH. Office of Dietary Supplements. Medical Encyclopedia: Vitamin B12 DHHS. NIH. NLM. MedlinePlus. Vitamin B12 Oregon State University. Linus Pauling Institute. Micronutrient Information Center.
DHHS. NIH. Office of Dietary Supplements.
DHHS. NIH. NLM. MedlinePlus.
Oregon State University. Linus Pauling Institute. Micronutrient Information Center.