The Japanese surnames etymology dictionary.
Shimane-ken Kanoashi-gun Tsuwano-chou , Kumamoto-ken , Niigata-ken . Fukuoka-ken Chikujou-gun Kouge-machi The day of Omoose Tama Kumagi tells that Mr. Kumagai's descendant Mr. Kumagi built up in 1240 (the first year of Inhei ). There is Nippon Kanzan in the small story of the same place. 熊谷 reference. Yamagata-ken Yamagata-shi Kasagi-machi was in the Edo period in the clan of the Yamagata of the Clan office.