Audio files were provided by John J. Farmer Jr., the Dean of Rutgers Law School-Newark and a senior counsel to the 9/11 Commission. Transcripts were edited from text provided by Miles L. Kara, Sr., a professional staff member of the 9/11 Commission. The call from Betty Ong was retrieved from an exhibit presented by the prosecution in United States v. Zacarias Moussaoui in United States District Court in Alexandria, Va.