@book{ BA58163117,
  author    = "Khinchin, Aleksandr I︠A︡kovlevich",
  title     = "Drei Perlen der Zahlentheorie",
  publisher = "Akademie-Verlag",
  year      = "1951",
  URL       = "https://ci.nii.ac.jp/ncid/BA58163117"
}