MEpedia:Dead links
From MEpedia, a crowd-sourced encyclopedia of ME and CFS science and history
Dead links are external links or links included in inline references to external websites that have moved, changed or removed content since the link was added to MEpedia. This phenomenon is known as link rot. A dead link should not automatically be deleted, as the material can often be retrieved using resources such as the Internet Archive. If you can find a working link to the same material, please do add that. Otherwise, you can add the Template tag “Dead link” after the link to signal that more research is needed to make the link functional again.