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Origin defines the source metadata, where applicable, for ODM ItemRefs or ItemGroupRefs. Origin as a child element replaces the Origin attribute in ODM v1.3 that existing for exists for the ItemDef and ItemGroupDef elements. The Origin element is based on the def:Origin element in Define-XML v2.1 with the Trace-XML v1.0 extension, but does not include the def:DocumentRef child element. The SourceItems element contain SourceItem child elements that reference the source variables, if any, for a given ItemRef. SourceItem elements provide machine-readable traceability and identify specific arguments for a MethodDef when used with an Origin with Type="Derived".
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