There are five copies of the Bologna manuscript, all of which have sections omitted. They are held by libraries in Paris, Nantes, Valencia, Rennes and Oxford. Frederick II may have lost an illuminated copy of the "De arte venandi cum avibus" at the Battle of Parma in 1248. In a letter dating from 1264–1265 addressed to Charles I of Anjou, the Milanese merchant Guilielmus Bottatus offered to sell two large volumes that had once belonged to Frederick II. The volumes are described as containing text discussing dogs, falcons and their diseases. This description only partially matches the contents of the surviving copies of the "De arte venandi cum avibus" and some scholars have suggested that the letter may have been referring to other manuscripts.