We prove the Finite Model Property (FMP) for Distributive Full Lambek Calculus (DFL) whose algebraic semantics is the class of distributive residuated lattices (DRL). The problem was left open in [8,5]. We use the method of nuclei and quasiembedding in the style of [10, 1].

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Purpose-The goal of this article was to define the concept of business survivability on the basis of a review of subject literature, as well as to identify the main determinants influencing the survivability of micro and small businesses based on an analysis of empirical studies that most often included a five-year observation of an enterprise-from the moment of its establishment, until it was deregistered, or the observation period was over. Design/Methodology/Approach-The author utilises a review of Polish and foreign subject literature, as well as secondary research regarding the survivability of micro and small businesses in the 20 th and 21 st centuries. Findings-The results suggest significant differences in business survivability depending on the country of origin of a given enterprise. The factors determining business survivability were divided into micro and macroeconomic, and their presence is vital for the company to persevere in turbulent market conditions. Originality/Value-This article is a compilation of definitions of business survivability across foreign and Polish studies of micro and small businesses after 2000. The paper compares the results of business survivability in Poland and western countries.

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We study the sequent system mentioned in the author's work [18] as CyInFL with 'intuitionistic' sequents. We explore the connection between this system and symmetric constructive logic of Zaslavsky [40] and develop an algebraic semantics for both of them. In contrast to the previous work, we prove the strong completeness theorem for CyInFL with 'intuitionistic' sequents and all of its basic variants, including variants with contraction. We also show how the defined classes of structures are related to cyclic involutive FL-algebras and Nelson FL ew -algebras. In particular, we prove the definitional equivalence of symmetric constructive FL ewc -algebras (algebraic models of symmetric constructive logic) and Nelson FL ew -algebras (algebras introduced by Spinks and Veroff [33], [34] as the termwise equivalent definition of Nelson algebras). Because of the strong completeness theorem that covers all basic variants of CyInFL with 'intuitionistic' sequents, we rename this sequent system to symmetric constructive full Lambek calculus (SymConFL). We verify the decidability of this system and its basic variants, as we did in the case of their distributive cousins [18]. As a consequence we obtain that the corresponding theories of (distributive and nondistributive) symmetric constructive FL-algebras are decidable.