@inbook{4332,
  author       = {Barton, Nicholas H and Hewitt, Godfrey},
  booktitle    = {Evolution and Speciation},
  editor       = {Atchley, William and Woodruff, David},
  isbn         = {9-780-5212-3823-6},
  pages        = {109 -- 145},
  publisher    = {Cambridge University Press},
  title        = {{Hybrid zones and speciation}},
  year         = {1981},
}