@book{ BN10723371,
  author    = "小松, 勇作 ",
  title     = "自然科学と数学 : 微分方程式",
  publisher = "ダイヤモンド社",
  year      = "1962",
  series    = "新初等数学講座",
  number    = ". 数学の応用 ; I ; 第5分冊",
  URL       = "https://ci.nii.ac.jp/ncid/BN10723371"
}