1.  54
    The Degrees Below a 1-Generic Degree $.Christine Ann Haught - 1986 - Journal of Symbolic Logic 51 (3):770 - 777.
    It is shown that the nonrecursive predecessors of a 1-generic degree $ are all 1-generic. As a corollary, it is shown that the 1-generic degrees are not densely ordered.
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  2.  24
    Undecidability and Initial Segments of the (R.E.) TT-Degrees.Christine Ann Haught & Richard A. Shore - 1990 - Journal of Symbolic Logic 55 (3):987-1006.
  3.  24
    Automorphisms in the PTIME-Turing Degrees of Recursive Sets.Christine Ann Haught & Theodore A. Slaman - 1997 - Annals of Pure and Applied Logic 84 (1):139-152.
    We consider questions related to the rigidity of the structure R, the PTIME-Turing degrees of recursive sets of strings together with PTIME-Turing reducibility, pT, and related structures; do these structures have nontrivial automorphisms? We prove that there is a nontrivial automorphism of an ideal of R. This can be rephrased in terms of partial relativizations. We consider the sets which are PTIME-Turing computable from a set A, and call this class PTIMEA. Our result can be stated as follows: There is (...)
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