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  1.  10
    A Note on Closed Degrees of Difficulty of the Medvedev Lattice.Caterina Bianchini & Andrea Sorbi - 1996 - Mathematical Logic Quarterly 42 (1):127-133.
    We consider some nonprincipal filters of the Medvedev lattice. We prove that the filter generated by the nonzero closed degrees of difficulty is not principal and we compare this filter, with respect to inclusion, with some other filters of the lattice. All the filters considered in this paper are disjoint from the prime ideal generated by the dense degrees of difficulty.
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  2.  27
    A Note on the Enumeration Degrees of 1-Generic Sets.Liliana Badillo, Caterina Bianchini, Hristo Ganchev, Thomas F. Kent & Andrea Sorbi - 2016 - Archive for Mathematical Logic 55 (3-4):405-414.
    We show that every nonzero Δ20\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\Delta^{0}_{2}}$$\end{document} enumeration degree bounds the enumeration degree of a 1-generic set. We also point out that the enumeration degrees of 1-generic sets, below the first jump, are not downwards closed, thus answering a question of Cooper.
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  3.  27
    Reducibility in Some Categories of Partial Recursive Operators.Caterina Bianchini & Andrea Sorbi - 1992 - Zeitschrift fur mathematische Logik und Grundlagen der Mathematik 38 (1):349-359.
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  4.  3
    Reducibility in Some Categories of Partial Recursive Operators.Caterina Bianchini & Andrea Sorbi - 1992 - Mathematical Logic Quarterly 38 (1):349-359.
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