@book{ BA20726727,
  author    = "Mayer, Alfred Goldsborough",
  title     = "The Hydromedusae",
  publisher = "Carnegie Institution of Washington",
  year      = "1910",
  series    = "Carnegie Institution of Washington publication",
  number    = "No. 109 . Medusae of the world ; vol. 1-2",
  URL       = "http://ci.nii.ac.jp/ncid/BA20726727"
}