Okla. Stat. tit. 19, § 1213

At the time and place set for the hearing and consideration of the petition, the board of county commissioners shall ascertain whether proper notice has been given and whether the statements contained in the petition are true. If true, and if a majority of the members of the board of the district to which annexation is desired do not object to such statement, the board of county commissioners shall enter into its minutes such findings and shall set forth in the minutes a description of the new boundaries of such district. Thereafter, residents within the annexed territory shall be entitled to ambulance service.