\newcommand{\etalchar}[1]{$^{#1}$}
\begin{thebibliography}{ALM{\etalchar{+}}92}

\bibitem[ALM{\etalchar{+}}92]{AroraLundMotwaniSudanSzegedy}
S.~Arora, C.~Lund, R.~Motwani, M.~Sudan, and M.~Szegedy.
\newblock Proof verification and intractability of approximation problems.
\newblock In {\em Proc. 33th IEEE Symp. on the Foundations of Computer Sci.},
  pages 14--23, 1992.

\bibitem[BFL90]{BabaiFortnowLund}
L.~Babai, L.~Fortnow, and C.~Lund.
\newblock Nondeterministic exponential time has two-prover interactive
  protocols.
\newblock In {\em Proc. 31th IEEE Symp. on Foundations of Computer Sci.}, pages
  26--35, 1990.

\bibitem[BG70]{BookGreibach}
R.~Book and S.~Greibach.
\newblock Quasi-realtime languages.
\newblock {\em Math. Systems Theory}, 4:97--111, 1970.

\bibitem[BGS75]{BakerGillSolovay}
T.~Baker, J.~Gill, and R.~Solovay.
\newblock Relativization of the {P=NP?} question.
\newblock {\em SIAM Journal on Computing}, 4:431--442, 1975.

\bibitem[BT93]{BuhrmanTorenvliet}
H.~Buhrman and L.~Torenvliet.
\newblock On the cutting edge of relativization: The resource bounded injury
  method.
\newblock Technical report, Dept. of Computer Science, University of Toronto,
  1993.

\bibitem[CFS94]{CondonFeigenbaumLundShor}
A.~Condon, J.~Feigenbaum, and C.~Lundand~P. Shor.
\newblock Probabilistic checkable debate systems and nonapproximability of
  {PSPCAE}-hard functions.
\newblock {\em Chicago Journal of Theoretical Computer Science}, 1994.
\newblock Submitted.

\bibitem[Coo73]{Cook73}
S.~A. Cook.
\newblock A hierarchy for nondeterministic time complexity.
\newblock {\em Journal of Computer and System Sciences}, 7(4):343--353, 1973.

\bibitem[CS76]{ChandraStockmeyer}
A.~K. Chandra and L.~Stockmeyer.
\newblock Alternation.
\newblock In {\em Proc. 17th IEEE Symp. on Foundations of Computer Sci.}, pages
  98--108, 1976.

\bibitem[FT95]{BuhrmanFortnowTorenvliet}
H.~Buhrman~L. Fortnow and L.~Torenvliet.
\newblock Using autoreductions to separate complexity classes.
\newblock In {\em Proc. 36th IEEE Symp. on Foundations of Computer Sci.}, pages
  520--527, 1995.

\bibitem[GJ79]{GareyJohnson}
M.~Garey and D.~Johnson.
\newblock {\em Computers and Intractability: A Guide to the Theory of
  NP-Completeness}.
\newblock W. H. Freeman, San Francisco, 1979.

\bibitem[HLS65]{HartmanisLewisStearns}
J.~Hartmanis, P.~Lewis, and R.~Stearns.
\newblock Hierarchies of memory limited computation.
\newblock In {\em Proc. 6th IEEE Symp. on Switching Circuit Theory and Logical
  Design.}, pages 179--190, 1965.

\bibitem[HS65]{HartmanisStearns}
J.~Hartmanis and R.~Stearns.
\newblock On the computational complexity of algorithms.
\newblock {\em Trans. American Math. Society}, 117:285--306, 1965.

\bibitem[KLR{\etalchar{+}}94]{KiwiLundRussellSpielmanSundaram}
M.~Kiwi, C.~Lund, A.~Russell, D.~Spielman, and R.~Sundaram.
\newblock Alternation in interaction.
\newblock In {\em Proc. 9th IEEE Struct. Complexity Theory Conf.}, pages
  294--303, 1994.

\bibitem[Kre88]{Krentel}
M.~Krentel.
\newblock The complexity of optimization problems.
\newblock {\em Journal Computer Systems Sci.}, 36:490--509, 1988.

\bibitem[Moc93]{Mocas}
S.~E. Mocas.
\newblock {\em Separating Exponential Time Classes From Polynomial Time
  Classes}.
\newblock PhD thesis, College of Computer Science , Northeastern University,
  September 1993.

\bibitem[Moc96]{Mocas2}
S.~E. Mocas.
\newblock Separating classes in the exponential-time hierarchy from classes in
  {PH}.
\newblock {\em Theoretical Computer Science}, 158:221--231, 1996.

\bibitem[SFM73]{SeiferasFischerMeyer}
J.~I. Seiferas, M.~J. Fischer, and A.~R. Meyer.
\newblock Refinements of nondeterministic time and space hierarchies.
\newblock In {\em Proc. 14th IEEE Symposium on Switching and Automata Theory},
  pages 130--137, 1973.

\bibitem[Sha90]{Shamir}
A.~Shamir.
\newblock {IP} = {PSPACE}.
\newblock In {\em Proc. 31st IEEE Symp. on Foundations of Computer Sci.}, pages
  11--15, 1990.

\bibitem[Sto83]{Stockmeyer}
L.~Stockmeyer.
\newblock The complexity of approximate counting.
\newblock In {\em Proc. 15th ACM Symp. on Theory of Computing}, pages 118--126,
  1983.

\end{thebibliography}
