Japanese Studies

 Kokugo gogen jiten 
国語語源辞典
EA Ref: PL663 .Y3 1976
Spine title is Zoku Kokugo gogen jiten.

Nihon gogen daijiten
日本語源大辞典
EA PL663 .N54 2005

Jikun
字訓
EA Ref:PL675.S57 1995
A dictionary of documenting the Japanese use of Chinese characters used in early Japanese texts. Includes about 1821 words. Useful for studying the importation of characters into Japan and how they were used in Japan.

Kanji Networks http://www.kanjinetworks.com/
An online etymological dictionary of kanji. Covers 4,500 Chinese characters as used in Japan.