Polynomial-size Frege and resolution proofs of <i>st</i>-connectivity and Hex tautologies.

Samuel R. Buss Polynomial-size Frege and resolution proofs of <i>st</i>-connectivity and Hex tautologies. 35-52 2006 357 Theor. Comput. Sci. 1-3 http://dx.doi.org/10.1016/j.tcs.2006.03.011 db/journals/tcs/tcs357.html#Buss06