Okla. Stat. tit. 12, § 3006
The contents of voluminous writings, recordings or photographs which cannot conveniently be examined in court may be presented in the form of a chart, summary or calculation. The originals, or duplicates, shall be made available for examination or copying, or both, by other parties at a reasonable time and place. The judge may order that they be produced in court.
Laws 1978, SB 276, c. 285, § 1006, eff. October 1, 1978.