Comment by Beijinger

Greek|Latin -> Arabic -> Latin

His pupil, the English scholastic Daniel of Morley, recorded one of Gerhard's methods[6] in translation: His Mozarabic assistant Ghalib (Latinized Galippus)[7] translated the text orally into medieval Castilian, Gerhard listened and wrote the text down in Latin. In the case of the Almagest, which had been translated from its original language of Ancient Greek first into Syriac, then into Arabic, and which Gerhard translated into Latin via the oral route of Castilian, this long chain of transmission introduced numerous sources of error.