Refer to:
Reed., D.P. Naming and synchronization in a decentralized computer system.
PhD thesis, Massachusetts Institute of Technology, 1978. Available as
Technical Report MIT/LCS/TR-205. 

See A repost of a message from Andreas Raab on May 6, 2003 below.

>From the abstract:

In this dissertation, a new approach to the synchronization of accesses to
shared data objects is developed. Traditional approaches to the
synchronization problems of shared data accessed by concurrently running
computations have relied on mutual exclusion -- the ability of one
computation to stop the execution of other computations that might access or
change shared data accessed by that computation. Our approach is quite
different. We regard an object that is modifiable as a sequence of immutable
versions, each version is the state of the object after an update is made to
the oblect. Synchronization can then be treated as a mechanism for naming
versions to be read and for defining where in the sequence of versions the
version resulting from some update should be placed. In systems based on
mutual exclusion, the timing of accesses selects the versions accessed. In
the system developed here called NAMOS, versions have two component names
consisting of the name of an object and a pseudo-time, the name of the
system state to which the version belongs. By giving programs control over
the pseudo-time in which access is made, synchronization of accesses to
multiple objects is simplified. 
Cont'd......

Fom Andreas Raab on May 6, 2003
--------------------------------------------
For those of you interested...

> -----Original Message-----
> From: David P. Reed [mailto:dpreed at reed.com]
> Sent: Tuesday, May 06, 2003 5:24 PM
> To: Andreas Raab
> Subject: Re: FW: David P Reed's Naming and synchronization in 
> a decentralized computer system
> 
> 
> It's my Ph.D. thesis.   A scanned image PDF is available 
> (couple hundred
> scanned pages); in spare time[never] I'm OCR'ing it, but it's 
> not done yet 
> in that form.
> 
> It can be downloaded at:
> http://www.reed.com/MIT-LCS-TR-205.zip (10 MB > approx).
> 
> Feel
> free to forward to squeakdev, but hopefully not slashdot.
> 
> At 03:10 AM 5/6/2003 +0200, Andreas Raab wrote:
> >Just popped up on Squeak-Dev. As a matter of fact I'd be
> interested in this
> >myself ;-)
> >
> >Cheers,
> >   - Andreas
><snip>