thema subject categories - SERP Analysis

https://ns.editeur.org/thema/en

https://ns.editeur.org/thema/en/F

https://www.ingramspark.com/blog/enhance-visibility-of-your-titles-with-thema-subject-categories

https://www.consonance.app/docs/about-thema/

https://www.ingramcontent.com/publishers-blog/mastering-thema-essentials-for-publishers

https://bic.org.uk/resources/thema/

https://booknetcanada.atlassian.net/wiki/spaces/UserDocs/pages/8257659/Thema%2BBasics%2BSubject%2BCategories%2BQualifier%2BCodes%2BNational%2BQualifier%2BLists

https://amnet-systems.com/thema-developing-a-subject-category-scheme-for-a-global-book-trade-page-2/

https://www.booknetcanada.ca/blog/2021/4/19/using-thema-to-identify-diverse-content-in-product-metadata-worked-example-1

https://publishers.asn.au/Web/Web/Member-Resources/Support/Metadata-Tips/Understanding-Thema.aspx