:- use_module(library(semweb/rdf_db)). rdf_save_header(+Fd, 
+Options)
rdf_save_header(+Fd, 
+Options)Save an RDF header, with the XML header, DOCTYPE, ENTITY and opening the rdf:RDF element with appropriate namespace declarations. It uses the primitives from section 3.5 to generate the required namespaces and desired short-name. Options is one of:
rdf and rdfs 
are added to the provided List. If a namespace is not 
declared, the resource is emitted in non-abbreviated form.