The notion of a graph type T is introduced by a collection of axioms. A graph of type T (or T-graph) is defined as a set of edges, of which the struct...
The execution costs of various types of database queries, expressed in terms of linear recusive definitions, are evaluated for two common query evalua...
We show that many combinatorial algorithms which generate certain objects of a given size systematically, actually follow a simple pattern, when the o...
We introduce a hierarchy of operations on (finite and infinite) binary trees. The operations are obtained by successive repetition of one initial oper...
The paper focusses on the logical backgrounds of the Dijkstra-Scholten program development style for correct programs. For proving the correctness of...
