| Name | Info | Provider | Link |
|---|---|---|---|
| subscription/membership/fee required | Nature Publishing Group | https://doi.org/10.1203/PDR.0b013e3181b337b9 | |
| subscription/membership/fee required | Ovid Technologies, Inc. | http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=19581841.ui |