http://www.legislation.gov.uk/uksi/1991/491/signature/madeThe A1 London-Edinburgh-Thurso Trunk Road (North Shotton Slip Road) Order 1991Roads and highwaysRoad buildingKing's Printer of Acts of Parliament2011-07-04HIGHWAYS, ENGLAND AND WALESSigned by authority of the Secretary of State for TransportJ. A. OwenRegional Director Northern RegionDepartment of Transport28th February 1991