Name Info Provider Link
Vitamin A free resource MedlinePlus Health Information https://medlineplus.gov/vitamina.html
subscription/membership/fee required Ovid Technologies, Inc. http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=35778881.ui
free resource PubMed Central https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/35778881/
free resource Europe PubMed Central https://europepmc.org/abstract/MED/35778881
subscription/membership/fee required Wiley https://doi.org/10.1111/ics.12799