Chapter 5: COR Responsibilities, Page 36 (also Listed in FAR and FAR part 16.306)

Tracking Modifications The COR must:

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  Ensure that changes in the work, services, and resulting effects on delivery schedule are formalized in a written supplemental agreement or change order issued by the Contracting Officer. The contractor must not proceed with the changes until formally approved and documented.
  
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  Monitor financial management controls. Coordinate with Government resource managers on all actions relating to funding and changes in the contract.