Deirdre Wilson and Dan Sperber. 1988. Mood and the Analysis of non-declarative sentences. In J. Dancy, J.Moravcsik & C. Taylor (eds) (1988) Human agency: Language, duty and value. Stanford University Press, Stanford CA: 77-101.

“How are non-declarative sentences understood? How do they differ semantically from their declarative counterparts? Answers to these questions once made direct appeal to the notion of illocutionary force. When they proved unsatisfactory, the fault was diagnosed as a failure to distinguish properly between mood and force…”