Scenario: Server declines to delete target because there are references to it. Client must discover the references in order to delete them so that the target can be deleted.
Scenario: Server does not maintain referential integrity. Client wants to be a good citizen by checking for references before deleting a resource.
Scenario: DMS client wants to display a list of all collections that a target belongs to by reference, so that users can navigate to those collections to find related documents or see how the target resource is being used.