Development of the Domain Name System (1988) [pdf]
cseweb.ucsd.edu
cseweb.ucsd.edu
[1] https://gade.us/thesis/naming-the-net.pdf there is also a web version
Ironically, hosts files are still passed around today, but for blocking purposes instead [0]
[0]: https://raw.githubusercontent.com/StevenBlack/hosts/master/h...
If you're curious what they look like, [0] has a bunch of old hosts files.
I would use accounts that people had just given me at places like Goddard, Arpa, Ames and copy their hosts file. I would sort and uniq them, and go through them by hand for sanity, and then update our machines.
I assume other people did the same.