A recompile of the "John Lions Commentary on the 6th edition Unix OS" book, along with the readily available source code. Grabbed from (http://v6.cuzuco.com/).
It's not perfect but it's the best I could do in the time that I have. This is much more cleaner to look at and print than the currently available PDF version.
Using MiKTeX (https://miktex.org/) through TexStudio. (https://sourceforge.net/projects/texstudio/)
This is all readily available online, no copyright infringement intended, I simply recompiled the book from the available .tex files.