1. A relational theory of datatypes;Backhouse,1990
2. A relational theory of datatypes, Eindhoven University of Technology;Backhouse,1992
3. Demonic operators and monotype factors;Backhouse,1992
4. Also Eindhoven University of Technology, Department of Computing Science, Computing Science Note No. 92/11.
5. A calculus for recursive program schemes;de Bakker,1973