Name Info Provider Link
subscription/membership/fee required Elsevier Science https://linkinghub.elsevier.com/retrieve/pii/S0304-3959(06)00183-7
Pain free resource MedlinePlus Health Information https://medlineplus.gov/pain.html
subscription/membership/fee required Ovid Technologies, Inc. http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=16697113.ui
subscription/membership/fee required Wolters Kluwer https://doi.org/10.1016/j.pain.2006.03.017