Hierarchical administrative subdivision codes (HASC) are codes to represent names of country subdivisions, such as states, province, regions.
They are described in the book Administrative Subdivisions of Countries: A Comprehensive World Reference, 1900 Through 1998, written by Gwillim Law.
The codes are alphabetic and have constant length for the first level subdivisions. Examples:
DE - Germany DE.NW - North Rhine-Westphalia DE.NW.CE - Kreis CoesfeldReferences
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