@techreport{weko_19890_1,
   author	 = "古川,哲也",
   title	 = "データの多重分類階層の構成",
   year 	 = "1998",
   institution	 = "九州大学経済学部",
   number	 = "57(1998-DBS-116)",
   month	 = "jul"
}