1. E. Astesiano, H.-J. Kreowski, B. Krieg-Bruckner (eds.) Algebraic Foundations of System Specification, Springer-Verlag, To appear.
2. H. Barendregt: Typed λ-calculi, in Handbook of Logic in Computer Science (S. Abramski et. al, eds.), Oxford Univ. Press 1993.
3. Lect Notes Comput Sci;R.M. Burstall,1980
4. Ph. D. Thesis;M.V. Cengarle,1994
5. H.-D. Ehrich. On the theory of specification, implementation and parameterization of abstract data types. J. of the ACM 29, 209–277, (1982)