Recommended language to use when contacting a publisher after manuscript has appeared in a peer reviewed journal:
The NIH Public Access Policy mandates that all researchers who receive NIH funding and publish peer-reviewed articles in scientific journals are required to deposit the final peer-reviewed manuscript into PubMed Central. These articles have not yet been deposited into PubMed Central. I’m not trying to suggest that [PUBLISHER] is solely responsible for these articles not being deposited. Ultimately, the PI is solely responsible for ensuring materials are submitted to PubMed Central, but I would appreciate any help you could offer in this matter.