If the judge is satisfied that the matter requires investigation, a citation must be issued to the executor or administrator, requiring him to appear, at a time and place to be therein specified to show cause why he should not give further security. Notice of the citation together with a copy thereof must be mailed by certified mail to the executor or administrator and his attorney of record, if any, at least five (5) days before the return day. If he has absconded, or cannot be found, it may be served by leaving a copy of it at his last place of residence, or by such publication as the judge may order.
Okla. Stat. tit. 58, § 180