Rdf Primer / quote 48 of 55
Intermediate URIrefs for structured values
Structured information like this is represented in RDF by considering the aggregate thing to be described (like John Smith's address) as a resource, and then making statements about that new resource. So, in the RDF graph, in order to break up John Smith's address into its component parts, a new node is created to represent the concept of John Smith's address, with a new URIref to identify it [...] This way of representing structured information in RDF can involve generating numerous "intermediate" URIrefs such as exaddressid:85740 to represent aggregate concepts such as John's address. Such concepts may never need to be referred to directly from outside a particular graph, and hence may not require "universal" identifiers. In addition, in the drawing of the graph representing the group of statements shown in Figure 5, the URIref assigned to identify "John Smith's address" is not really needed, since the graph could just as easily have been drawn as in Figure 6: