Here is where the preservation policies are defined. 1. Items will be retained indefinitely. 2. The repository will try to ensure continued readability and accessibility: Items will be migrated to new file formats where necessary. It may not be possible to guarantee the readability of some unusual file formats. 3. The repository regularly backs up its files according to current best practice. 4. The original bitstream is retained for all items, in addition to any upgraded formats. 5. Items may be removed at the request of the author/copyright holder. 6. Acceptable reasons for withdrawal include: Proven copyright violation or plagiarism Legal requirements and proven violations National Security Falsified research 7. Withdrawn items are not deleted per se, but are removed from public view. 8. Withdrawn items' identifiers/URLs are retained indefinitely. 9. URLs will continue to point to 'tombstone' citations, to avoid broken links and to retain item histories, with: A link to a replacement version, where available A note explaining the reasons for withdrawal 10. Errata and corrigenda lists may be included with the original record if required. 11. If necessary, an updated version may be deposited: The earlier version may be withdrawn from public view. There will be links between earlier and later versions, with the most recent version clearly identified. 12. Items are allocated a checksum to facilitate the detection of alterations. 13. In the event of the repository being closed down, the database will be transferred to another appropriate archive. This article was published on 2024-08-21