| Name | Info | Provider | Link |
|---|---|---|---|
| subscription/membership/fee required | Ovid Technologies, Inc. | http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=15503830.ui | |
| subscription/membership/fee required | Springer | https://doi.org/10.1023/B:QURE.0000040788.12947.b9 |