1. This name is recent and is not used in many of our earlier papers.
2. Mereology’ is a term (first used by Legniewski) to describe the formal theory of part, whole and related concepts.
3. Ladkin (1986) has investigated temporal non convex interval logics. The spatial logic we present below will also allow non-convex spatial entities.
4. This problem has already been noted in a temporal context (Galton, 1990).
5. Alternatively, non empty regular closed sets of connected Ta-spaces have been proved to be models for the RCC axiom set (Gotts, 1996a).