When you look at the product offerings and product specifications ressources, they have the exact same CategoryRef sub-resource definition.
Also, Category is a sub-resource for the Catalog resource. Catalog resource is not exclusive to product offerings. the API polymorphism allows entities in collections to inherit properties from a base entity. For example, a Product Catalog, a Ressource Catalog, a ProductSpec Catalog inherit properties from the base Catalog entity.
In the TMF620 user guide, page 28 says "catalogType = Type of this Catalog, like Product, Service, Resource, etc.)
It's a small defect in TMF620. The Category Resource should have a ProductSpecificationRef sub-resource.
You can just fix it yourself by adding a new sub-ressource.
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Kind regards,
Matthieu Hattab
Lyse Platform
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