Generating a usage report
Right-click the item, and select Report > Usage.
The items and diagrams that use the item you right-clicked are listed in the Results pane:
Diagrams on which the item appears.
Items that use the item as a type or data type.
Items that are linked to the item
Items and diagrams that reference the item through model object references in their rich text.
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You cannot generate a usage report for a diagram.