Rabbi Yitzchak, the author of the Itur, composed his book in the year 4942 and some say afterwards [(Tzeda)], it is written [Shomer HaDat, letter 55, section 2] Rabbeinu Yitzchak bar Avan of Marseilles composed Sefer HaItur, and composed Sefer Itur Sofrim. And a composition on the Rif of one hundred gates and the Ten Commandments, thus I saw in Sefer Sha'arei Tzion, and in the Hagahot, the 5th of Ishut, chapter 5 of the Rambam...