1. Alencar, A.J., Goguen, J.A.: OOZE: An Object Oriented Z Environment. In: ECOOP 1991 - V European Conference on Object-Oriented Programming, Geneva - Switzerland, Springer, Heidelberg (1991)
2. Meyer, B.: Object-Oriented Software Construction, 2nd edn. Prentide-Hall (1997)
3. Stroustrup, B.: The C++ Programming Language, 3rd edn. Addison-Wesley, Reading (1997)
4. de, V.A., Cordeiro, O.: From MooZ to Eiffel: A Rigorous Approach to System Development. Master’s thesis, Universidade Federal de Pernambuco, Departmento de Informática (1994) (in Portuguese)
5. C. A. R. Hoare Series Editor;D.A. Watt,1989