On Tue, 19 Sep 2017 14:43:59 -0400, Chet Ramey <chet.ramey at case.edu> wrote:
> On 9/19/17 2:32 PM, Chet Ramey wrote:
> > As I understand it, Scheifler began with W, which Paul Asente and Chris
> > Kent had ported to Unix and given him a copy. He initially replaced its
> > synchronous protocol with an asynchronous one and went on from there.  
> 
> This is covered in one of the original Athena papers: The X Window System
> by Scheifler and Gettys. I have the full set of "Project Athena: The First
> Ten Years"; it's in volume 1. I think that paper was presented at a
> couple of conferences, so there are probably copies floating around on the
> net somewhere.

E.g. in the ACM’s Digital Library: http://dl.acm.org/citation.cfm?id=24053
(from ACM Transactions on Graphics Volume 5 Issue 2).

Regards,

Stephen