Work authorization system in OPA or EEF?

Work authorization system is part of EEF or OPA?

Andy crowe says WAS is part of PMIS and PMIS is part of EEF.But PMBOK says WAS is in OPA(page  no 33)

 If you read the line in page 33 properly, it says the procedure for work authorization and not the work authorization system itslef.

"Procedures for prioritizing, approving, and issuing work authorizations."

work authorization system will be a part of PMIS and in turn a part of EEF.

yes you are right...thanks..