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  1. Andrzej Sendlewski (1995). Axiomatic Extensions of the Constructive Logic with Strong Negation and the Disjunction Property. Studia Logica 55 (3):377 - 388.
    We study axiomatic extensions of the propositional constructive logic with strong negation having the disjunction property in terms of corresponding to them varieties of Nelson algebras. Any such varietyV is characterized by the property: (PQWC) ifA,B V, thenA×B is a homomorphic image of some well-connected algebra ofV.We prove:• each varietyV of Nelson algebras with PQWC lies in the fibre –1(W) for some varietyW of Heyting algebras having PQWC, • for any varietyW of Heyting algebras with PQWC the least and the (...)
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  2. Janusz Czelakowski, Alasdair Urquhart, Ryszard Wójcicki, Jan Woleński, Andrzej Sendlewski & Marcin Mostowski (1990). Books Received. [REVIEW] Studia Logica 49 (1):151-161.
  3. Andrzej Sendlewski (1990). Nelson Algebras Through Heyting Ones: I. Studia Logica 49 (1):105 - 126.
    The main aim of the present paper is to explain a nature of relationships exist between Nelson and Heyting algebras. In the realization, a topological duality theory of Heyting and Nelson algebras based on the topological duality theory of Priestley ([15], [16]) for bounded distributive lattices are applied. The general method of construction of spaces dual to Nelson algebras from a given dual space to Heyting algebra is described (Thm 2.3). The algebraic counterpart of this construction being (...)
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  4. Andrzej Sendlewski (1984). Some Investigations of Varieties of N -Lattices-Lattices. Studia Logica 43 (3):257-280.
    We examine some extensions of the constructive propositional logic with strong negation in the setting of varieties of $\mathcal{N}$ -lattices. The main aim of the paper is to give a description of all pretabular, primitive and preprimitive varieties of $\mathcal{N}$ -lattices.
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