| Name | Info | Provider | Link |
|---|---|---|---|
| Vitamin D | free resource | MedlinePlus Health Information | https://medlineplus.gov/vitamind.html |
| subscription/membership/fee required | Ovid Technologies, Inc. | http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=22181684.ui | |
| free resource | PubMed Central | https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/22181684/ | |
| free resource | Europe PubMed Central | https://europepmc.org/abstract/MED/22181684 | |
| subscription/membership/fee required | Wiley | https://doi.org/10.1902/jop.2011.110346 |