Name Info Provider Link
subscription/membership/fee required Elsevier Science https://linkinghub.elsevier.com/retrieve/pii/S1525-8610(12)00223-X
Disabilities free resource MedlinePlus Health Information https://medlineplus.gov/disabilities.html
free resource PubMed Central https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/22863663/
free resource Europe PubMed Central https://europepmc.org/abstract/MED/22863663