It doesn't matter which combinations are supported by Libreoffice, it can be used by other software too. It's the official spelling for: - Netherlands (including Bonaire, Sint Eustatius en Saba) - Belgium - Suriname
Aruba, Curaçao, and Sint Maarten also seem to be part of the Netherlands, but are a different country, and they have Dutch as one of the official languages there. They seem to collaborate with the rest, but it's unclear that they use the same spelling, my guess is not. Kurt