Morton, Adam [1999] 'Where Demonstratives Meet Vagueness: Possible Languages', Proceedings of the Aristotelian Society 99, pp. 1-18.

Abstract: I present three invented languages, in order to support a claim that vagueness and demonstrativity are related. One of them handles vagueness like English handles demonstratives, the second handles demonstratives like English handles vagueness, and the third combines the resources of the first two. The argument depends on the claim that all three can be learned and used by anyone who can speak English.