The following are additional sources of information.
Retraction Watch provides an informed commentary on Retracted journal articles, their authors, and publishers.
Organisations with a particular interest in the publication and research integrity and usually referenced by publishers.
The Retraction Guidelines issued by COPE (2019) set the standard for its members which includes most leading medical publishers.
Typically, publishers reference the COPE Retraction Guidelines 2009. These are examples are from major publishers: