1. S. Ahmad, Some results on the structure of the Σ 2 enumeration degrees, Recursive Function Theory Newsletter 38 (July, 1989), item 373.
2. S. Ahmad, Embedding the diamond in the Σ 2 enumeration degrees, to appear.
3. K. Ambos-Spies, Minimal pairs for polynomial time reducibilities, to appear.
4. L. Adleman and K. Manders, Reducibility, randomness, and intractibility, Proc. 9th ACM STOC (1977), 151–163.
5. T. Baker, J. Gill and R. Solovay, Relativizations of the P=NP? question, SIAM J. Comput. 4 (1975), 431–442.