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The cross-reference can be to an entire master data record (e.g. all of the properties for Mexico in the MDR):
"homeCountry": "/mdrmdrs/country:1v1/MEX",
Or for a specific property in the master data record (e.g. just the country name):
"homeCountry": "/mdrmdrs/country:1v1/MEX/name",
Defining a Cross-Reference in the modelSchema
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