c. Information is more reliable if it is
1) Obtained from sources independent of the engagement client, such as confirmations of receivables or expert appraisals that are timely and made by a source with no connection to the auditee.
2) Corroborated by other information.
3) Direct, such as the internal auditors personal observation, rather than indirect, such as hearsay.
4) An original document, not a copy.