The Rashba is Rabbeinu Shlomo ben Avraham ben Aderet, who took up his position in Barcelona in the year 5040, and he was a great sage in all the wisdoms, and Rabbeinu Yonah was his distinguished teacher and he also learned from the Ramban, and he authored Sefer Torat HaBayit, the long and the short, and Sefer Avodat HaKodesh [(Shomer HaDat)] and novellae on Berakhot, Chullin...