[1] H. Abelson and G.J. Sussman, Structure and Interpretation of Computer Programs, MIT Press, 1985.

[2] P. Aczel, Non-well-founded sets, CSLI Lecture Notes 14, Stanford, 1988.

[3] P. Aczel, Final Universes of Processes, in "MFPS’93 Conference Proceedings", Brookers et al. (eds.), Springer LNCS 802, New Orleans, 1993.

[4] P. Aczel, N. Mendler, A Final Coalgebra Theorem, in "Category Theory and Computer Science", D.H. Pitt et al. (eds.), Springer LCNS 389, 1989, pp. 357-365.

[5] M. Barr, Terminal coalgebras in well-founded set theory, "TCS", 114, 1993, pp. 299-315.

[6] M. Barr, Additions and corrections to ‘Terminal colagebras in well-founded set theory’, "TCS", 124, 1994, pp. 189-192.

[7] M. Barwise and L. Moss, Vicious circles: On the mathematics of non-wellfounded phenomena, CSLI Publications, Standford, 1996.

[8] M. Felleisen and D.P. Friedman, A syntactic theory of sequential state, "Theoretical Computer Science", 69/3, 1989, pp. 234-287.

[9] M. Forti and F. Honsell, Set theory with free construction principles, "Annali della Scuola Normale Superiore di Pisa", Cl. Sci. (4), 10, 1983, pp. 493-522.

[10] M. Forti and F. Honsell, Axioms of Choice and Free Construction Principles I, "Bulletin de la Societe Mathematique de Belgique", I ser.B, 36, 1984.

[11] M. Forti and F. Honsell, A general construction of Hyperuniverses, "TCS", 165, 1996.

[12] M. Forti, F. Honsell and M. Lenisa, Process and Hyperuniverses, in "MFPS’93 Conference Proceedings", I. Prívara et al. (eds.), Springer LNCS 841, Berlin, 1994, 352-361.

[13] M. Forti, F. Honsell and M. Lenisa, Axiomatic Characterizations of Hyperuniverses and Applications, "Annals of the New York Academy of Sciences", 80, Papers on General Topology and Applications, 11th Summer Conference University of Southern Maine, Gorham, 1996, pp. 140-163.

[14] P. Freyd and A. Scedrov, Categories, Allegories, North-Holland, Amsterdam, 1990.

[15] R. Harper, R. Milner and M. Tolfe, The Semantics of Standard ML, LFCS Report Series, LFCS87-36, Edinburgh, 1987.

[16] C. Hermida, B. Jacobs, Structural induction and coinduction in a fibrational setting, "Inf. and Comp.", 145, 1998, pp. 107-152

[17] F. Honsell and M. Lenisa, Final Semantics for Untyped Lambda Calculus, in "TLCA’95 Conference Proceedings, M. Dezani and G. Plotkin (eds.), Springer LCNS 902, Berlin, 1995, pp. 249-265.

[18] F. Honsell and M. Lenisa, Coinductive Characterizations of Applicative Structures, "Math. Struct. in Computer Science", 9, 1999, pp. 403-435.

[19] F. Honsell, M. Lenisa, U. Montanari, and M. Pistore, Semantics for the p-calculus, in "PROCOMET’98 Conference Proceedings", D. Gires et al. (eds.), Chapman & Hall, 1998.

[20] F. Honsell and S. Ronchi Della Rocca, Semantica Operazionale di un frammento del linguaggio SCHEME, Università di Torino-Università di Udine, 1989.

[21] B. Jacobs, Objects and Classes, co-algebraically, in "Object-Orientation with Parallelism and Book Persistence", B. Freitag et al. (eds.), Kluwer Academic Publishers, 1996.

[22] G. Kahn, Natural semantics, Proc. Symposium on Theoretical Aspects of Computer Science, Springer-Verlag, 1987.

[23] M. Lenisa, Final Semantics for Higher Order Concurrent Language, in "CAAP’96", H. Kirchner et al. (eds.), Springer LNCS 1059, 1996, pp. 102-118.

[24] M. Lenisa, Themes in Final Semantics, PhD Thesis TD-6/98, Dipartimento di Informatica, Università di Pisa, March, 1998.

[25] M. Lenisa, From Set-theoretic Coinduction to Coalgebraic Coinduction: some results, some problems, in "CMCS’99 Conference Proceedings", ENTCS 19, 1999, pp. 1-21.

[26] M. Lenisa, J. Power, H. Watanabe, Distributivity for endofunctors, pointed and co-pointed endofunctors, monads and comonads, in "CMCS’00 Conference Proceedings", ENTCS 33, 2000.

[27] I. Mason and C. Talcott, Equivalence in Functional with Effects, "J. Functional Programming", 1/2, 1991, pp. 287-328.

[28] R. Muller, M-LISP: A Representation-Independent Dialect of LISP with Reduction Semantics, in "ACM Trans. Programming Languages and Systems", 14/4, 1992 pp. 589-616.

[29] G. Plotkin, Structured Operational Semantics. DAIMI report series, Aarhus, Denmark, 1981.

[30] H. Reichel, An approach to objects semantics based on terminal co-algebras, "Math. Struct. in Computer Science", 5, 1995, pp. 129-152.

[31] J.J.M.M. Rutten, Universal coalgebra: a theory of systems, CS-R9652, CWI, 1996.

[32] J.J.M.M. Rutten and D. Turi, On th Foundations of Final Semantics: Non-Standard Sets, Metric Spaces, Partial Orders, in "REX Conference Proceedings", J. de Bakker et al. (eds.), Springer LNCS 666, 1993, pp. 477-530.

[33] J.J.M.M. Rutten and D. Turi, Initial algebra and final coalgebra semantics for concurrency: A Decade of Concurrency – Reflections and Perspectives, in "REX Conference Proceedings", J. de Bakker et al. (eds.), Spronger LNCS 803, 1994, pp. 530-582.

[34] J.J.M.M. Rutten and E. de Vink, Bisimulation for probabilistic transition systems: a coalgebraic approach (extended abstract), in "ICALP’97" Conference Proceedings", P. Degano et al. (eds.), Springer LCNS 1256, 1997, pp. 460-470.

[35] B.C. Smith, Reflexion and Semantics in Lisp, in "Proc. 11th ACM Symposium on Principle on Programming Languages", New York, 1994, pp. 23-35.

[36] D. Turi, Functorial Operational Semantics and its Denotational Dual, PhD Thesis, 1996.

[37] D. Turi and G. Plotkin, Towards a mathematical operational semantics, in "Proc. 12th LICS Conference IEEE", Computer Science Press, 1997, pp. 280-291.

[38] D. Turi and I. Rutten, On the foundations of final coalgebra semantics: non-wellfounded sets, partial orders, metric spaces, "Math. Struct. in Computer Science", 8, 1998, pp. 481-540.