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http://line.naver.jp/ja/
(access on October 29, 2013)
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(access on October 29, 2013)
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4. IFIP;R. Thawonmas,2008
5. Japan External Trade Organization: Content market in Germany, pp. 26–45 (2009),
http://www.jetro.go.jp/jfile/report/07000040/05001678.pdf
(access on October 29, 2013) (in Japanese)