EppHemTis-TR-90

@techreport{EppHemTis-TR-90,
title = {Probabilistic and unambiguous computation are incomparable},
author = {David Eppstein and Lane A. Hemachandra and James Tisdall and B{\"u}lent Yener},
institution = {Univ. of Rochester, Dept. of Computer Science},
number = {335},
year = {1990}}