Raavan
From Wikinoah English
Rav Eliezer the son of Natan was a Tosafist who lived in Germany from 1090 until 1170. His main work is entitled Even HaEzer, and is comprised of his halachic decisions, responsa, and a commentary on the prayerbook. He also wrote several liturgical poems. Among his students was his grandson Raavyah.
