1. Barr, M., Wells, C. (eds.): Category Theory for Computing Science, 2nd edn. Prentice Hall International (UK) Ltd., Upper Saddle River (1995)
2. Booth, R., Meyer, T., Varzinczak, I.J.: Next steps in propositional horn contraction. In: Boutilier, C. (ed.) Proceedings of the 21st International Joint Conference on Artificial Intelligence (IJCAI 2009), pp. 702–707 (2009)
3. Delgrande, J.P.: Horn clause belief change: contraction functions. In: Brewka, G., Lang, J. (eds.) Proceedings of the Eleventh International Conference on Principles of Knowledge Representation and Reasoning, KR 2008, pp. 156–165. AAAI Press (2008)
4. Diskin, Z., Wolter, U.: A diagrammatic logic for object-oriented visual modeling. Electron. Notes Theoret. Comput. Sci. 203(6), 19–41 (2008). Proceedings of the Second Workshop on Applied and Computational Category Theory (ACCAT 2007)
5. Van Ditmarsch, H., van Der Hoek, W., Kooi, B.: Dynamic Epistemic Logic, 1st edn. Springer, Heidelberg (2007)