Anyone at University of Waterloo ?

I'm an italian CS student, and I was looking for the following paper:

Lewis Denver Baxter
The Complexity of Unification
(Supervisor: T. Pietrzykowski)

The only places where I've found it are acm.org (but the links to
purchase a copy go nowhere) and University of Waterloo Library:

http://trellis1.tug-libraries.on.ca/cgi-bin/Pwebrecon.cgi?v1=1&ti=1,1&Search%5FArg=unification%20and%20complexity&SL=None&CNT=25&Search%5FCode=CMD%2A&PID=13251&SEQ=20061217030349&SID=1

I'm only intersted in an algorithm that the author uses to prove that
the Subsumption problem is NP-complete (a book, Computers and
Intractability- A Guide to the Theory of NP-completeness, says that
Baxter proves it by reducing the problem to 3-SAT, that is well known
to be NP-complete)

Anyone could provide me that algorithm ?

Thanks a lot in advance.
Best regards.

.