[1] 九龍城砦 - Wikipedia (11/11/2017, 8:27:55 AM) <https://ja.wikipedia.org/wiki/%E4%B9%9D%E9%BE%8D%E5%9F%8E%E7%A0%A6>
[2] うんこ飛地 (yoshida著, 5/27/2006, 8:36:44 PM) <http://www.geocities.jp/keropero2003/tobichi/tobichiunko.html>
[3] インフラ飛び地 (yoshida著, 6/23/2012, 4:57:07 PM) <http://www.geocities.jp/keropero2003/zatsu/infra.html#09>
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