@book{ BA32419780,
  author    = "Jacobson, Paul B. and Reavis, William C.",
  title     = "Duties of school principals",
  publisher = "Prentice-Hall",
  year      = "1941",
  series    = "The Prentice-Hall education series",
  number    = "",
  URL       = "https://ci.nii.ac.jp/ncid/BA32419780"
}