- Department of Mathematical Sciences,
Northern Illinois University,
DeKalb, IL 60115.
- Department of Mathematics,
Naval Postgraduate School,
Monterey, CA 93940.
- Department of Mathematics and Computer Science,
Kent State University,
Kent, OH 44242.
Research supported by a National Research Council
fellowship and NSF grant DMS-9002884.
Tue Feb 14 12:51:53 CST 1995