צדה לדרך לר' מנחם זרח זיע"א' " ", ". " ", " " ", " " ". . " " " " " " " " " " : , . , . Tzeidah laDerech by Rabbi Menachem ben Zerach The book Tzeidah laDerech on the laws of Niddah and Taharah by Rabbi Menachem ben Zerach, student of Rabbi Yehuda son of the Rosh. This revised edition includes source references called "Tziyunim laDerech", notes from the writings of Rabbi Ovadia Yosef zt"l called "Darchei Yosef", and excellent compilations on matters of holiness and purity