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Heinrich, Patrick (2013). "Hōgen ronsō: the great Ryukyuan languages debate of 1940". Contemporary Japan. 25 (2): 167–187. doi:10.1515/cj-2013-0008. S2CID142189448.
Heinrich, Patrick (2013). "Hōgen ronsō: the great Ryukyuan languages debate of 1940". Contemporary Japan. 25 (2): 167–187. doi:10.1515/cj-2013-0008. S2CID142189448.