1. Goguen J., Thatcher J., Wagner E.: “An initial algebra approach to the specification, correctness, and implementation of abstract data types”, Current Trends in Programming Methodology, Vol.4, Yeh Ed. Prentice Hall, 1978 (also IBM Report RC 6487, Oct. 1976).
2. Ehrig H., Kreowski H., Thatcher J., Wagner J., Wright J.: “Parameterized data types in algebraic specification languages”, Proc. 7th ICALP, July 1980.
3. Bernot G.: “Une sémantique algébrique pour une spécification différenciée des exceptions et des erreurs: application à l'implémentation et aux primitives de structuration des spécifications formelles”, Thèse de troisième cycle, Université de Paris-Sud, Orsay, 1985.
4. Bidoit M.: “Algebraic data types: structured specifications and fair presentations”, Proc. of AFCET Symposium on Mathematics for Computer Science, Paris, March 1982.
5. Ehrig H., Kreowski H., Mahr B., Padawitz P.: “Algebraic implementation of abstract data types”, Theoretical Computer Science, Oct. 1980.