| Name | Info | Provider | Link |
|---|---|---|---|
| subscription/membership/fee required | Ovid Technologies, Inc. | http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=21857232.ui | |
| subscription/membership/fee required | Wolters Kluwer | https://doi.org/10.1097/ID.0b013e31822f7b97 |