@article {6634,
	title = {Structural explanations in syntactic variation: The evolution of English negative and polarity indefinites},
	journal = {Language Variation and Change},
	volume = {30},
	year = {2018},
	pages = {83{\textendash}107},
	author = {Heather Burnett and Koopman, Hilda and Tagliamonte, Sali A}
}
