The contents of a public record, or of a document authorized to be recorded or filed and actually recorded or filed, including data compilations in any form, if otherwise admissible, may be proved by duplicate, certified as correct in accordance with Code Section 24-9-902 or Code Section 24-9-920 or testified to be correct by a witness who has compared it with the original. If a duplicate which complies with this Code section cannot be obtained by the exercise of reasonable diligence, then other evidence of the contents may be given.
OCGA § 24-10-1005