A more formal treatment of a less simple example.- Stationary behaviour of some ternary networks.- Finding the correctness proof of a concurrent program.- On the interplay between mathematics and programming.- A theorem about odd powers of odd integers.- In honour of Fibonacci.- On the foolishness of "natural language programming".- Program inversion.- The Schorr-Waite graph marking algorithm.- Eliminating the chaff.- Proofs, programs and their development — The axiomatic approach.- Current ideas in programming methodology.- Basic axiomatic definitions.- The multiple assignment statement.- Is sometimes ever better than always?.- A case study in language design: Euclid.- Proof rules for the programming language Euclid.- Verification of Euclid programs.- Specifications and proofs for abstract data types in concurrent programs.- Specification and verification of a network mail system.- From specification to implementation — The formal approach.- Program development by stepwise transformations — The project CIP.- Systematics of transformation rules.- Special transformation techniques.- A study on transformational semantics.- Detailization and lazy evaluation, infinite objects and pointer representation.- Examples for change of types and object structures.- Development of the Schorr-Waite algorithm.- A derivation-oriented proof of the Schorr-Waite marking algorithm.- Languages as tools — Interactive program construction.- Programing languages for reliable computing systems.- Programming methodology and language implications.- Towards a wide spectrum language to support program specification and program development.- Semantics of nondeterministic and noncontinuous constructs.- Notes on type abstraction.- Some theoretical aspects of program construction.