Arabic version of the De sphaericis (كتاب الأكر) by Theodosius of Bithynia (ثاودوسيوس; Θεοδοìσιος; c 160-c 100 BC). The preface (f. 1v, lines 3-5, transcribed below) states that it was translated from Greek into Arabic by Qusṭā ibn Lūqā (قسطا بن لوقا; ca 820-912), up to Chapter 3, figure 5, at t...