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What differentiates Thema from BISAC or BIC is Thema supports both international and national marketing of books while BISAC and BIC represent the subject needs of a single market. Thema does this by combining a single international Subject Category list with six Qualifier Code lists. Each Qualifier Code lists provide generic values common to all markets, but when appropriate Qualifier lists can include country specific codes – National Extensions -- that allow each list to be subdivided as granularity granular as the individual country needs. (See Thema Basics for details) Other countries (or markets) can use or ignore that detail because the code system is hierarchical and the source "international codes" are always available. Thema works for international markets and each country can personalize the lists for use within their own supply chain.
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