Etymology and distribution of 旧澤.

Furusawa 【旧澤】^{レベル1
Very rare}  The Japanese surnames etymology dictionary.

Toukyou-to Nerima-ku , Saitama-ken . Toukyou-to Nerima-ku Nanta Naka is based. Saitama-ken Iruma-shi In Shinku tells that it was written as "Tani" in the Edo period. 谷次 Yatsugi reference.