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Concepts are represented by a rectangle, containing the name of the concept as shown below.

Concept element

The name used must be the concept's fully specified name or a synonym.

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Optionally the definition status of a concept may be represented. Concepts that are fully defined may be represented using a double line border as shown below:

Defined concept element

A rectangle with a single border is assumed to be primitive unless explicitly noted otherwise or it is clear in context (e.g., diagramming during a whiteboard discussion).

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