Aulus Gellius (Noctes Atticae, vi. 17), Ammianus Marcellinua (xxii. 16), and Orosius (l. vi. c. 15). They all speak in the past tense, and the words of Ammianus are remarkably strong:
fuerunt Bibliothecae
innumerabiles; et loquitum monumentorum veterum concinens
fides, etc.