Bulletin of the Section of Logic 10/3 (1981)details


Table of contents




  • 1. Janis CIRULIS, On the EK-fragments of positive and classical propositional calculus100

  • 2. Ewa GRACZYNSKA, On regular and symmetric identities104

  • 3. Marek PALASINSKI and Barbara WOZNIAKOWSKA, An equational basis for commutative BCK-algebras108

  • 4. Wieslaw DZIOBIAK, On matrices characteristic of relevant logics113

  • 5. Teodor STEPIEN, Craig-Godel-Lindenbaum's property and Sobicinski-Tarski's property in propositional calculi116

  • 6. Hien Huy BUI and Istvan NEMETI, Problems with the category theoretic notions of ultraproducts122

  • 7. Andrzej WRONSKI, Splittings of lattices of quasivarieties128

  • 8. Andrzej WRONSKI, Quasivarieties of Heyting algebras130

  • 9. Jacek K.KABZINSKI, On equivalential fragment of the implicative extentional consequence135