—  The published PDF and HTML are the version of record and are not changed silently.

—  Any change after publication is made through a linked, dated correction notice.

An article is removed only in exceptional cases: content that is defamatory, infringes legal rights, is subject to a court order, or poses a serious risk to health or safety. The title and authors remain, with a note explaining the removal.

When an article must be replaced, the original is retracted with a notice and the corrected version is published with a link to that notice and to the original.

Earlier versions held by authors in repositories should link to the version of record via its DOI.

Correction & Retraction · Expressions of Concern · Self-Archiving · Electronic Archiving