@techreport{weko_61350_1,
   author	 = "永田,健太郎 and 久保山,哲二",
   title	 = "特許の有効性に影響を与える要因の検討",
   year 	 = "2009",
   institution	 = "東京大学, 学習院大学",
   number	 = "11(2009-EIP-43)",
   month	 = "feb"
}