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  1. Asher M. Kach, Karen Lange & Reed Solomon (2013). Degrees of Orders on Torsion-Free Abelian Groups. Annals of Pure and Applied Logic 164 (7-8):822-836.
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  2. Peter A. Cholak, Peter M. Gerdes & Karen Lange (2012). On N-Tardy Sets. Annals of Pure and Applied Logic 163 (9):1252-1270.
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  3. Paola D'Aquino, Julia Knight & Karen Lange (2011). Limit Computable Integer Parts. Archive for Mathematical Logic 50 (7-8):681-695.
    Let R be a real closed field. An integer part I for R is a discretely ordered subring such that for every ${r \in R}$ , there exists an ${i \in I}$ so that i ≤ r < i + 1. Mourgues and Ressayre (J Symb Logic 58:641–647, 1993) showed that every real closed field has an integer part. The procedure of Mourgues and Ressayre appears to be quite complicated. We would like to know whether there is a simple procedure, (...)
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  4. Karen Lange (2010). A Characterization of the 0 -Basis Homogeneous Bounding Degrees. Journal of Symbolic Logic 75 (3):971-995.
    We say a countable model has a 0-basis if the types realized in are uniformly computable. We say has a (d-)decidable copy if there exists a model ≅ such that the elementary diagram of is (d-)computable. Goncharov, Millar, and Peretyat'kin independently showed there exists a homogeneous model with a 0-basis but no decidable copy. We extend this result here. Let d ≤ 0' be any low₂ degree. We show that there exists a homogeneous (...)
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  5. Karen Lange (2008). The Degree Spectra of Homogeneous Models. Journal of Symbolic Logic 73 (3):1009-1028.
    Much previous study has been done on the degree spectra of prime models of a complete atomic decidable theory. Here we study the analogous questions for homogeneous models. We say a countable model A has a d-basis if the types realized in A are all computable and the Turing degree d can list $\Delta _{0}^{0}$ -indices for all types realized in A. We say A has a d-decidable copy if there exists a model B ≅ A such that the elementary (...)
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  6. Karen Lange & Robert I. Soare (2007). Computability of Homogeneous Models. Notre Dame Journal of Formal Logic 48 (1):143-170.