1. http://www.nlm.nih.gov/medlineplus/druginfo/natural/313.html
2. http://en.wikipedia.org/wiki/Biotin
3. http://www.webmd.com/vitamins-and-supplements/lifestyle-guide-11/supplement-guide-biotin
4. http://www.wisegeek.com/what-is-allantoin.htm
5. http://www.thesage.com/catalog/products/Allantoin.html
6. http://en.wikipedia.org/wiki/Allantoin
7. http://www.anyvitamins.com/vitamin-b5-pantothenic-info.htm
8. http://lpi.oregonstate.edu/infocenter/vitamins/pa/
9. http://en.wikipedia.org/wiki/Pantothenic_acid