On Oct 6, 2018 ,jnc@mercury.lcs.mit.edu (Noel Chiappa) wrote:

Date: Sat,  6 Oct 2018 21:04:59 -0400 (EDT)
From: jnc@mercury.lcs.mit.edu (Noel Chiappa)
Subject: Re: [TUHS] Unix source code archive in the news
Message-ID: <20181007010459.9098E18C096@mercury.lcs.mit.edu>

If not, what am I missing? The Berkeley Genie OS for the SDS? (Dunno if that's
been saved.) The THE system? (Ditto - although I know someone has saved the
last X8.) The Atlas OS?

The Computer History Museum’s Donald Knuth digital archive project  (http://www.computerhistory.org/collections/catalog/102726297) contains a scan of a listing of the source code of the THE Operating System by Bron, Dijkstra, et al. The finding aid for the collection is here: http://archive.computerhistory.org/resources/text/Knuth_Don_X4100/PDF_index/KnuthDigitalArchive-Index.html — scan down for “Source code of the THE Operating System”.