| Name | Info | Provider | Link |
|---|---|---|---|
| subscription/membership/fee required | Nature Publishing Group | https://doi.org/10.1203/01.PDR.0000059221.40073.82 | |
| subscription/membership/fee required | Ovid Technologies, Inc. | http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=12621122.ui |