1 2 Tashiro, Kazui. "Foreign Relations During the Edo Period: Sakoku Reexamined." Journal of Japanese Studies. Vol. 8, No. 2, Summer 1982.
1 2 Toby, Ronald. State and Diplomacy in Early Modern Japan. Princeton: Princeton University Press, 1984
↑ Toby, Ronald (1977). "Reopening the Question of Sakoku: Diplomacy in the Legitimation of the Tokugawa Bakufu", Journal of Japanese Studies. Seattle: Society for Japanese Studies.
↑ Hall, J. (1955). Tanuma Okitsugu, 1719-1788, p. 105.
↑ K. Jack Bauer, A Maritime History of the United States: The Role of America's Seas and Waterways, University of South Carolina Press, 1988., p. 57
