| Name | Info | Provider | Link |
|---|---|---|---|
| CYP2A6 | free resource | BioCyc | https://metacyc.org/gene?orgid=META&id=HS10343 |
| subscription/membership/fee required | Ovid Technologies, Inc. | http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=11960914.ui | |
| subscription/membership/fee required | Silverchair Information Systems | https://academic.oup.com/carcin/article-lookup/doi/10.1093/carcin/23.4.611 |