1. Introduction to Functional Programming;Bird,1988
2. Relational program derivation and context-free language recognition;Bird,1994
3. J. Peterson et. al. Report on the programming language Haskell (version 1.3). Technical Report YALEU/DCS/RR-1107, Yale University, 1996.
4. Maarten M. Fokkinga. Law and Order in Algorithmics. PhD thesis, Universiteit Twente, The Netherlands, 1992.
5. M.M. Fokkinga. Monadic maps and folds for arbitrary datatypes. Memoranda Informatica 94-28, University of Twente, June 1994.