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3. Minimal pairs for polynomial time reducibilities;Ambos-Spies,1987
4. K. Ambos-Spies, A. Nies, The theory of the polynomial time many-one degrees is undecidable, STACS 1992, pp. 209–218.
5. BPP has subexponential simulations unless EXPTIME has publishable proofs;Babai;Comput. Complexity,1993