This paper covers three separate topics. All three concern Cicero and his first-century AD commentator Q. Asconius Pedianus. The chief contribution of parts one and two is to identify sources consulted by Asconius that have previously not been revealed or suspected. Part one will show that the multiple errors committed by Asconius in recounting the circumstances of the death of Cicero’s daughter Tullia in 45 BC are to be attributed to a source that misunderstood a letter of Cicero. Prior to publication, the letters to Atticus appear to have been accessible in a private archive, and on at least one, and probably two occasions, Asconius reveals that the historian Fenestella was misled by identifiable letters of Cicero to Atticus. Therefore, i...