@incollection{barth1967,
  author    = {Barth, F.},
  booktitle = {Themes in Economic Anthropology},
  editor    = {Firth, R.},
  key       = {Barth (1967)},
  pages     = {149-174},
  series    = {Association for Social Anthropology Monographs},
  title     = {Economic Spheres in Darfur},
  volume    = {6},
  year      = {1967}
}