Dr Alex Citkin is the CIO of Metropolitan Telecommunications, New York. Before joining Metropolitan Telecommunications he was Director of Research and Development of EDI Corporation New York.Dr Alexei Muravitsky is Professor of Mathematics at Louisiana Scholars' College at Northwestern State University of Louisiana. From 1980 to 1991 he was a Senior Research Scientist at the Institute of Mathematics and Computer Science of the Academy of Sciences of the Moldovan SSR and from 1992 to 1999 he was a Visiting Member at the Courant Institute of Mathematical Sciences at New York University.

• 1: Introduction 2: Preliminaries 3: Sentential Formal Languages 4: Logical Consequences 5: Matrix Consequences 6: Unital Abstract Logics 7: Equational Consequence 8: Equational L-Consequence 9: Q-Consequence 10: Decidability Bibliography Index

Dr Alex Citkin is the CIO of Metropolitan Telecommunications, New York. Before joining Metropolitan Telecommunications he was Director of Research and Development of EDI Corporation New York.Dr Alexei Muravitsky is Professor of Mathematics at Louisiana Scholars' College at Northwestern State University of Louisiana. From 1980 to 1991 he was a Senior Research Scientist at the Institute of Mathematics and Computer Science of the Academy of Sciences of the Moldovan SSR and from 1992 to 1999 he was a Visiting Member at the Courant Institute of Mathematical Sciences at New York University.

• 1: Introduction 2: Preliminaries 3: Sentential Formal Languages 4: Logical Consequences 5: Matrix Consequences 6: Unital Abstract Logics 7: Equational Consequence 8: Equational L-Consequence 9: Q-Consequence 10: Decidability Bibliography Index

Dr Alex Citkin is the CIO of Metropolitan Telecommunications, New York. Before joining Metropolitan Telecommunications he was Director of Research and Development of EDI Corporation New York.Dr Alexei Muravitsky is Professor of Mathematics at Louisiana Scholars' College at Northwestern State University of Louisiana. From 1980 to 1991 he was a Senior Research Scientist at the Institute of Mathematics and Computer Science of the Academy of Sciences of the Moldovan SSR and from 1992 to 1999 he was a Visiting Member at the Courant Institute of Mathematical Sciences at New York University.

• 1: Introduction 2: Preliminaries 3: Sentential Formal Languages 4: Logical Consequences 5: Matrix Consequences 6: Unital Abstract Logics 7: Equational Consequence 8: Equational L-Consequence 9: Q-Consequence 10: Decidability Bibliography Index