1. Principles of OBJ2;Futatsugi,1985
2. Introducing OBJ;Goguen,2000
3. J. Goguen, Theorem proving and algebra, [Unpublished Book], now being planned to be up on the web for the free use.
4. CafeOBJ Report: The Language, Proof Techniques, and Methodologies for Object-oriented Algebraic Specification;Diaconescu,1998
5. Logical foundations of CafeOBJ;Diaconescu;Theor. Comput. Sci.,2002