Okla. Stat. tit. 51, § 51-60: Hearing and summons

The Senate, when sitting as a court of impeachment, shall

appoint a day for hearing the impeachment, and the accused shall be

required by a summons by the clerk to appear on that day. The

summons shall be served by delivering a copy of the same and of the

articles of impeachment to the accused, in person if to be found, or

by leaving the copies at his residence with some member of his

family over sixteen (16) years of age.