@book{7311,
	author = {Walker, James A.},
	title = {Variation in linguistic systems /},
	publisher = {Routledge,},
	year = {2010.},
	address = {New York, NY :},
	url = {http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=018887066&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA}
}