@book{ BA84117751,
  author    = "Vareschi, Volkmar and Instituto Botánico (Venezuela)",
  title     = "Helechos",
  publisher = "Instituto Botanico",
  year      = "1968",
  series    = "Flora de Venezuela",
  number    = "v. 1",
  URL       = "http://ci.nii.ac.jp/ncid/BA84117751"
}