and shall be marked in such a manner as to indicate the specific type of governmental unit operating the vehicle. These markings shall be prominently displayed and shall consist of one of the following appropriate legends: 'STATE,' 'CITY,' 'COUNTY,' 'AUTHORITY,' or 'BOARD.' In addition, each such license plate shall bear a county identification strip indicating the county in which the vehicle is based, except that vehicles owned by the state shall not be required to bear such county identification strip.
OCGA § 40-2-37