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  1.  13 DLs
    Claude Laflamme & Jian-Ping Zhu (1998). The Rudin-Blass Ordering of Ultrafilters. Journal of Symbolic Logic 63 (2):584-592.
    We discuss the finite-to-one Rudin-Keisler ordering of ultrafilters on the natural numbers, which we baptize the Rudin-Blass ordering in honour of Professor Andreas Blass who worked extensively in the area. We develop and summarize many of its properties in relation to its bounding and dominating numbers, directedness, and provide applications to continuum theory. In particular, we prove in ZFC alone that there exists an ultrafilter with no Q-point below in the Rudin-Blass ordering.
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  2.  7 DLs
    Andreas Blass & Claude Laflamme (1989). Consistency Results About Filters and the Number of Inequivalent Growth Types. Journal of Symbolic Logic 54 (1):50-56.
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  3.  6 DLs
    Claude Laflamme (1996). A Few Special Ordinal Ultrafilters. Journal of Symbolic Logic 61 (3):920-927.
    We prove various results on the notion of ordinal ultrafilters introduced by J. Baumgartner. In particular, we show that this notion of ultrafilter complexity is independent of the more familiar Rudin-Keisler ordering.
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  4.  6 DLs
    Claude Laflamme & Marion Scheepers (1999). Combinatorial Properties of Filters and Open Covers for Sets of Real Numbers. Journal of Symbolic Logic 64 (3):1243-1260.
    We analyze combinatorial properties of open covers of sets of real numbers by using filters on the natural numbers. In fact, the goal of this paper is to characterize known properties related to ω-covers of the space in terms of combinatorial properties of filters associated with these ω-covers. As an example, we show that all finite powers of a set R of real numbers have the covering property of Menger if, and only if, each filter on ω associated with its (...)
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  5.  4 DLs
    William S. Hatcher & Claude Laflamme (1983). On the Order Structure of the Hyperreal Line. Mathematical Logic Quarterly 29 (4):197-202.
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  6.  4 DLs
    Claude Laflamme (1990). Upward Directedness of the Rudin-Keisler Ordering of P-Points. Journal of Symbolic Logic 55 (2):449-456.
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  7.  2 DLs
    Claude Laflamme (2001). Bartoszynski Tomek. On the Structure of Measurable Filters on a Countable Set. Real Analysis Exchange, Vol. 17 No. 2 (1992), Pp. 681–701. Bartoszynski Tomek and Shelah Saharon. Intersection of Archive for Mathematical Logic, Vol. 31 (1992), Pp. 221–226. Bartoszynski Tomek and Judah Haim. Measure and Category—Filters on Ω. Set Theory of the Continuum, Edited by Judah H., Just W., and Woodin H., Mathematical Sciences Research Institute Publications, Vol. 26, Springer-Verlag, New York, Berlin, Heidelberg .. [REVIEW] Bulletin of Symbolic Logic 7 (3):388-389.
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  8.  1 DLs
    Jeremy Avigad, Sy Friedman, Akihiro Kanamori, Elisabeth Bouscaren, Philip Kremer, Claude Laflamme, Antonio Montalbán, Justin Moore & Helmut Schwichtenberg (2007). Montréal, Québec, Canada May 17–21, 2006. Bulletin of Symbolic Logic 13 (1).
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  9.  1 DLs
    Claude Laflamme (1989). Forcing with Filters and Complete Combinatorics. Annals of Pure and Applied Logic 42 (2):125-163.
    We study ultrafilters produced by forcing, obtaining different combinatorics and related Rudin-Keisler ordering; in particular we answer a question of Baumgartner and Taylor regarding tensor products of ultrafilters. Adapting a method of Blass and Mathias, we show that in most cases the combinatorics satisfied by the ultrafilters recapture the forcing notion in the Lévy model.
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  10.  1 DLs
    Saharon Shelah, Claude Laflamme & Bradd Hart (1993). Models with Second Order Properties V: A General Principle. Annals of Pure and Applied Logic 64 (2):169-194.
    Shelah, S., C. Laflamme and B. Hart, Models with second order properties V: A general principle, Annals of Pure and Applied Logic 64 169–194. We present a general framework for carrying out the construction in [2-10] and others of the same type. The unifying factor is a combinatorial principle which we present in terms of a game in which the first player challenges the second player to carry out constructions which would be much easier in a generic extension of the (...)
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  11.  0 DLs
    Claude Laflamme (1994). Bounding and Dominating Number of Families of Functions on Ω. Mathematical Logic Quarterly 40 (2):207-223.
    We pursue the study of families of functions on the natural numbers, with emphasis here on the bounded families. The situation being more complicated than the unbounded case, we attack the problem by classifying the families according to their bounding and dominating numbers, the traditional scheme for gaps. Many open questions remain.
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  12.  0 DLs
    Claude Laflamme (2011). S. Todorcevic, Introduction to Ramsey Spaces. Bulletin of Symbolic Logic 17 (2):269.
  13.  0 DLs
    T. Bartoszynski & Claude Laflamme (2001). REVIEWS-Five Papers. Bulletin of Symbolic Logic 7 (3):388-389.
     
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  14.  0 DLs
    Claude Laflamme (2001). [Omnibus Review]. Bulletin of Symbolic Logic 7 (3):388-389.
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