Okla. Stat. tit. 19, § 35

The meeting of the boards of county commissioners herein provided for shall be called by the chairman of the board of commissioners of the county to which said territory has been transferred, to meet in the county seat of said county not less than sixty (60) days from the date of issuance of the Governor's proclamation declaring said territory legally transferred, and said chairman shall give ten (10) days' written notice to each of the county commissioners of the said counties specifying the time and place of said meeting and shall be continued from day to day until their labors are concluded.