Backups (tarballs, archives, torrents, data:URIs, etc) - sgml/signature GitHub Wiki
http://www.emailarchivestaskforce.org/documents/managing-email-for-preservation/
Web
https://www.loc.gov/preservation/digital/formats/fdd/fdd000235.shtml
https://en.wikipedia.org/wiki/Web_ARChive
https://en.wikipedia.org/wiki/Text_Encoding_Initiative
https://www.backblaze.com/blog/cloud-storage-durability/
https://documentation.cpanel.net/display/70Docs/Backup+Tarball+Contents
https://archive.org/details/bittorrent
https://www.wired.com/story/gawker-archives-freedom-of-press-foundation-toast-la-weekly/
https://www.wired.com/2015/10/cyphon-wired-archive-migration/
https://news.ycombinator.com/item?id=17433173
https://www.w3.org/MarkUp/Wilbur/
StackExchange
https://www.reddit.com/r/programming/comments/ae9sq/stackoverflow_backup_procedures/
https://stackoverflow.blog/2009/12/13/blog-outage-backup-policies/