Aelius Donatus
Between 1450 and 1455, Gutenberg printed several texts, some of which remain unidentified; his texts did not bear the printer's name or date, so attribution is possible only from typographical evidence and external references. Certainly several church documents including a papal letter and two indulgences were printed, one of which was issued in Mainz. In view of the value of printing in quantity, seven editions in two styles were ordered, resulting in several thousand copies being printed. Some printed editions of "Ars Minor", a schoolbook on Latin grammar by Aelius Donatus, may have been printed by Gutenberg; these have been dated either 1451–52 or 1455.