1. Burmeister, P.: A Model Theoretic Oriented Approach to Partial Algebras. Akademie-Verlag, Berlin (1986)
2. Cerioli, M.: Relationships between Logical Formalism. PhD thesis, Università de Pisa–Genova–Udine (1993)
3. Gogolla, M., Drosten, K., Lipeck, U., Ehrich, H.-D.: Algebraic and operational semantics of specifications allowing exceptions and errors. Theoretical Computer Science 34, 289–313 (1984)
4. Goguen, J.A., Thatcher, J.W., Wagner, E.G.: An initial algebra approach to the specification, correctness, and implementation of abstract data types. In: Yeh, R.T. (ed.) Current Trends in Programming Methodology, IV, Data Structuring, pp. 80–149. Prentice-Hall, Englewood Cliffs (1978)
5. International Series of Monographs on Computer Science;I. Horebeek Van,1989