1. Understanding Utterances. An Introduction to Pragmatics;Blakemore,1992
2. Politeness: Some Universals in Language Usage;Brown,1987
3. More on approximations;Channell;Journal of Pragmatics,1980
4. Vagueness as a conversational strategy;Channell;Nottingham Linguistic Circular,1985
5. Vague Language;Channell,1994