AMC M.A.610 Maintenance work orders    

CAA ORS9 Decision No. 1

‘A written work order’ may take the form of, but not limited to, the following:

— A formal document or form specifying the work to be carried out. This form may be provided by the continuing airworthiness management organisation managing the aircraft, or by the maintenance organisation undertaking the work, or by the owner/operator himself;

— An entry in the aircraft log book specifying the defect that needs to be corrected.