Searle, J. R. (1969) Speech Acts. Cambridge: Cambridge University Press. Doi: https://doi.org/10.1017/CBO9781139173438.
Trosborg, A. (1995) Interlanguage Pragmatics: Requests, Complaints and Apologies. Berlin: Mouton de Gruyter. Doi: https://doi.org/10.1515/9783110885286.