Beckmann, A., & BUSS, S. R. (2009). POLYNOMIAL LOCAL SEARCH IN THE POLYNOMIAL HIERARCHY AND WITNESSING IN FRAGMENTS OF BOUNDED ARITHMETIC. Journal of Mathematical Logic, 09(01), pp. 103-138. doi:10.1142/S0219061309000847

Beckmann, Arnold, and SAMUEL R. BUSS. "POLYNOMIAL LOCAL SEARCH IN THE POLYNOMIAL HIERARCHY AND WITNESSING IN FRAGMENTS OF BOUNDED ARITHMETIC." Journal of Mathematical Logic 09, no. 01 (2009): 103-138.

Beckmann, Arnold, and SAMUEL R. BUSS. "POLYNOMIAL LOCAL SEARCH IN THE POLYNOMIAL HIERARCHY AND WITNESSING IN FRAGMENTS OF BOUNDED ARITHMETIC." Journal of Mathematical Logic 09.01 (2009): 103-138.