@book{ BA42670003,
  author    = "Cullmann, Oscar and Boring, M. Eugene",
  title     = "Unity through diversity : its foundation, and a contribution to the discussion concerning the possibilities of its actualization",
  publisher = "Fortress Press",
  year      = "1988",
  URL       = "http://ci.nii.ac.jp/ncid/BA42670003"
}