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  1. George Epstein & Helena Rasiowa (1995). A Partially Ordered Extention of the Integers. Studia Logica 54 (3):303 - 332.
    This paper presents a monotonic system of Post algebras of order +* whose chain of Post constans is isomorphic with 012 ... -3-2-1. Besides monotonic operations, other unary operations are considered; namely, disjoint operations, the quasi-complement, succesor, and predecessor operations. The successor and predecessor operations are basic for number theory.
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  2. Helena Rasiowa (1994). Axiomatization and Completeness of Uncountably Valued Approximation Logic. Studia Logica 53 (1):137 - 160.
  3. Helena Rasiowa (1994). Cecylia Rauszer. Studia Logica 53 (4):467 - 471.
  4. Nguyen Cat Ho & Helena Rasiowa (1989). Plain Semi-Post Algebras as a Poset-Based Generalization of Post Algebras and Their Representability. Studia Logica 48 (4):509 - 530.
    Semi-Post algebras of any type T being a poset have been introduced and investigated in [CR87a], [CR87b]. Plain Semi-Post algebras are in this paper singled out among semi-Post algebras because of their simplicity, greatest similarity with Post algebras as well as their importance in logics for approximation reasoning ([Ra87a], [Ra87b], [RaEp87]). They are pseudo-Boolean algebras generated in a sense by corresponding Boolean algebras and a poset T. Every element has a unique descending representation by means of elements in a corresponding (...)
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  5. Nguyen Cat Ho & Helena Rasiowa (1987). Semi-Post Algebras. Studia Logica 46 (2):149 - 160.
    In this paper, semi-Post algebras are introduced and investigated. The generalized Post algebras are subcases of semi-Post algebras. The so called primitive Post constants constitute an arbitrary partially ordered set, not necessarily connected as in the case of the generalized Post algebras examined in [3]. By this generalization, semi-Post products can be defined. It is also shown that the class of all semi-Post algebras is closed under these products and that every semi-Post algebra is a semi-Post product of some generalized (...)
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  6. Nguyen Cat Ho & Helena Rasiowa (1987). Subalgebras and Homomorphisms of Semi-Post Algebras. Studia Logica 46 (2):161 - 175.
    Semi-Post algebras have been introduced and investigated in [6]. This paper is devoted to semi-Post subalgebras and homomorphisms. Characterization of semi-Post subalgebras and homomorphisms, relationships between subalgebras and homomorphisms of semi-Post algebras and of generalized Post algebras are examined.
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  7. Helena Rasiowa (1985). Topological Representations of Post Algebras of Order Ω+ and Open Theories Based on Ω+-Valued Post Logic. Studia Logica 44 (4):353 - 368.
    Post algebras of order + as a semantic foundation for +-valued predicate calculi were examined in [5]. In this paper Post spaces of order + being a modification of Post spaces of order n2 (cf. Traczyk [8], Dwinger [1], Rasiowa [6]) are introduced and Post fields of order + are defined. A representation theorem for Post algebras of order + as Post fields of sets is proved. Moreover necessary and sufficient conditions for the existence of representations preserving a given set (...)
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  8. Helena Rasiowa (1981). On Logic of Complex Algorithms. Studia Logica 40 (3):289 - 310.
    An algebraic approach to programs called recursive coroutines — due to Janicki [3] — is based on the idea to consider certain complex algorithms as algebraics models of those programs. Complex algorithms are generalizations of pushdown algorithms being algebraic models of recursive procedures (see Mazurkiewicz [4]). LCA — logic of complex algorithms — was formulated in [11]. It formalizes algorithmic properties of a class of deterministic programs called here complex recursive ones or interacting stacks-programs, for which complex algorithms constitute mathematical (...)
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  9. Helena Rasiowa (1979). Algorithmic Logic. Multiple-Valued Extensions. Studia Logica 38 (4):317 - 335.
    Extended algorithmic logic (EAL) as introduced in [18] is a modified version of extended +-valued algorithmic logic. Only two-valued predicates and two-valued propositional variables occur in EAL. The role of the +-valued logic is restricted to construct control systems (stacks) of pushdown algorithms whereas their actions are described by means of the two-valued logic. Thus EAL formalizes a programming theory with recursive procedures but without the instruction CASE.The aim of this paper is to discuss EAL and prove the completeness theorem. (...)
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  10. Helena Rasiowa & Wiktor Marek (1977). In Memory of Andrzej Mostowski. Studia Logica 36 (1-2):1 - 8.
  11. Helena Rasiowa (1975). Mixed-Valued Predicate Calculi. Studia Logica 34 (3):215 - 234.
  12. Helena Rasiowa (1974). An Algebraic Approach to Non-Classical Logics. Warszawa,Pwn - Polish Scientific Publishers.
    Provability, Computability and Reflection.
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  13. Helena Rasiowa (1963). The Mathematics of Metamathematics. Warszawa, Państwowe Wydawn. Naukowe.
     
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  14. S. Łuszczewska-Romahnowa, Helena Rasiowa, Stanisław Kamiński & Laudwik Borkowski (1958). Recenzje. Studia Logica 8 (1):319-333.
  15. Helena Rasiowa (1956). Review: B. U. Pil'cak, On the Calculus of Problems. [REVIEW] Journal of Symbolic Logic 21 (4):372-372.
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  16. Helena Rasiowa (1955). On a Fragment of the Implicative Propositional Calculus. Studia Logica 3 (1):225-226.
  17. Helena Rasiowa (1955). O Pewnym Fragmencie Implikacyjnego Rachunku Zdań. Studia Logica 3 (1):208 - 226.
  18. Helena Rasiowa (1954). Review: Roman Sikorski, A Note to Rieger's Paper "On Free $Aleph_xi$-Complete Boolean Algebras.". [REVIEW] Journal of Symbolic Logic 19 (4):287-287.
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  19. Helena Rasiowa & Andrze Mostowski (1953). A Geometric Interpretation of Logical Formulae. Studia Logica 1 (1):273-275.
    The aim of this paper is to give a geometric interpretation of quantifiers in the intutionistic predicate calculus. We obtain it treating formulae withn free variables as functions withn arguments which run over an abstract set whereas the values of functions are open subsets of a suitable topological space.
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  20. Helena Rasiowa & Andrzeij Mostowski (1953). O Geometrycznej Interpretacji Wyrażeń Logicznych. Studia Logica 1 (1):254 - 275.
  21. Helena Rasiowa (1952). Review: Eugen Gh. Mihailescu, Researches on Sub-Systems of the Propositional Calculus. [REVIEW] Journal of Symbolic Logic 17 (4):277-278.
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  22. Helena Rasiowa (1951). Review: B. U. Pil'cak, On the Decision Problem for the Calculus of Problems. [REVIEW] Journal of Symbolic Logic 16 (3):226-227.
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