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↑ジュリアン・ロッシュ (2014).国際米貿易.エルゼビア・サイエンス. p. 193. ISBN9781845692841。
↑ Suk Hi Kim; Kenneth A Kim (2014). Global Corporate Finance: A Focused Approach (2nd ed.). World Scientific Publishing Company . pp. 98–100 . ISBN9789814618021。