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Hisashi Suzuki, The Head-Burial Site in the Numazu City and the Skulls of the Medieval Japanese, in Journal of the Anthropological Society of Nippon 97 (1989), Volume 97, pp. 23-37. https://doi.org/10.1537/ase1911.97.23 Turnbull, Stephen (2012-01-20). Samurai Women 1184–1877. Bloomsbury Publishing. pp. 38–40. ISBN978-1-84603-952-2.