1. D. Achlioptas, A. Naor, and Y. Peres, “Rigorous Location of Phase Transitions in Hard Optimization Problems,” Nature, Volume 435 (2005) pp. 759–764.
2. L. Berman and J. Hartmanis, “On Isomorphisms and Density of NP and Other Complete Sets,” SIAM Journal on Computing, Volume 6, Issue 2 (1977) pp. 305–322.
3. N. J. Cerf, L. K. Grover, and C. P. Williams, “Nested Quantum Search and Structured Problems,” Phys. Rev. A, Volume 61 (2000) 032303.
4. P. Cheeseman, B. Kanefsky, and W. M. Taylor, “Where the Really Hard Problems Are,” in Proc. of International Joint Conference on Artificial Intelligence (IJCAI’91), Sydney, Morgan Kauffman, San Mateo (1991) pp. 331–337.
5. M. Davis, G. Logemann, and D. Loveland, “A Machine Program for Theorem Proving,” Comm. ACM, Volume 5 (1962) p. 394.