A version of this technical report has now been published in The
Third  ACM Symposium on the Foundations of Software Engineering
(FSE '95).  Copies of the paper may be requested via the
web at:

	http://www.cs.washington.edu/homes/gmurphy

or by request to either:

	Gail Murphy
	Department of Computer Science and Engineering
	University of Washington
	Box 352350
	Seattle, WA 98195-2350 USA  
	(Voice):  1.206.616.1847
	(Fax):    1.206.543.2969
	(E-mail): gmurphy@cs.washington.edu

or:

	David Notkin
	Department of Computer Science and Engineering
	University of Washington
	Box 352350
	Seattle, WA 98195-2350 USA  
	(Voice):  1.206.685.3798
	(Fax):    1.206.543.2969
	(E-mail): notkin@cs.washington.edu