1. J. Adámek, H. Herrlich and G. E. Strecker, Abstract and Concrete Categories, Wiley Interscience (New York, 1990).
2. M. Aiello, I. Pratt-Hartmann and J. van Benthem (Eds.), Handbook of Spatial Logics, Springer-Verlag (Berlin Heidelberg, 2007).
3. Ph. Balbiani (Ed.), Special issue on spatial reasoning, J. Appl. Non-Classical Logics, 12 (2002).
4. B. Bennett and I. Düntsch, Axioms, algebras and topology, in: M. Aiello, I. Pratt-Hartmann and J. van Benthem (Eds.), Handbook of Spatial Logics, Springer-Verlag (Berlin Heidelberg, 2007), pp. 99–160.
5. A. Cohn and S. Hazarika, Qualitative spatial representation and reasoning: an overview, Fundam. Inform., 46 (2001), 1–29.