BibTeX-Format:
@incollection{Klein 2009, year = {2009}, booktitle = {{D}escribing and {M}odeling {V}ariation in {G}rammar}, title = {{S}emi-modal variation}, typ = {incollection}, publisher = {Mouton de Gruyter}, pages = {297-323}, series = {Trends in Linguistics. Studies and Monographs