@inbook {2659,
	title = {Grammaticalisation and the English modals},
	booktitle = {Problems in the modality of natural language},
	year = {1991},
	month = {1991},
	pages = {9-27},
	publisher = {Pedagogical University of Opole},
	organization = {Pedagogical University of Opole},
	address = {Opole},
	keywords = {NG},
	author = {Anderson, John M.},
	editor = {Kakietek, Piotr}
}
