ספר התשב"ץSefer HaTashbetz
שו"ת מהרשב"ץ (תשב"ץ = תשובות שמעון בן צמח).Collection of over 900 responsa of the Rashbatz (Tashbetz is an acronym for "Teshuvot Shimon ben Tzemach"). In addition to halakhah, these correspondences cover many other facets of Judaism, including aggadah, philosophy, and astronomy.