Paper describing the processes of recovering historical versions, attribution, and creation of the repo: <a href="https://www.dmst.aueb.gr/dds/pubs/jrnl/2016-EMPSE-unix-history/html/unix-history.pdf" rel="nofollow">https://www.dmst.aueb.gr/dds/pubs/jrnl/2016-EMPSE-unix-histo...</a><p>If you only look at the GitHub repository, look at the branch listing.<p>(I'm not the author, just an admirer of the work.)