Actually, I was just thinking about ontology because that was the idea. But things are little bit different now. The thing is that I don’t have OWL file, in meantime I got mdb file. This file has few tables (Keyword, Metadata, MetadataAuthor…). So, tuples are even better in this case. I’ll have to choose from which fields I’ll create tuple, and this example that you gave me, will do the work. Thank you for comments.