free content
フリーコンテント
Digital rights
Open source
Free education
Free software movement
Freedom of information
Information wants to be free
Open publishing
Open-source hardware
Project Gutenberg Knowledge for free – The Emergence of Open Educational Resources. 2007, ISBN 92-64-03174-X.
/suto3/google.iconfree content
/suto3/Google画像検索.iconfree content
/suto3/Google定義検索.icon free content
/suto3/wikipedia.iconfree content
/suto3/weblio.icon free content
/suto3/kotobank.icon free content
/suto3/jisho.icon free content