A categorical treatment of pre- and post- conditions. - Colourings of planar maps and the equality of two languages. - On the equivalence of synchronization sets. - Inner and mutual compatibility of basic operations on module specifications. - Exact computation sequences. - An algebraic theory of flowchart schemes. - An algebraic formalism for graphs. - Membership for growing context sensitive grammars is polynomial. - Weighted graphs : A tool for logic programming. - Classical and incremental evaluators for attribute grammars. - Transformation strategies for deriving on line programs. - Probabilistic Ianov's schemes. - Alternating bottom-up tree recognizers. - Bottom-up recursion in trees. - Basic tree transducers. - Trie partitioning Limiting distributions. - Random walks, gaussian processes and list structures. - Random walks on trees. - Infinite trees, markings and well foundedness. - Computable directory queries. - Relating type-structures partial variations on a theme of Friedman and Statman. - On applications of algorithmic logic.