SELECT Calll.nu
FROM sparqltable( SELECT ?nu ?codice ? codicedue
		  WHERE{ 	?x rdf:type 'Calll'.
		       	?x :Caller ?z.
			?z rdf:type 'User'.
			?z :numberPhone ?nu.
			?z :Contract ?o.
			?o rdf:type 'Operator'.
			?o :cf ?codice.
			?x :Called ?w.
			?w rdf:type 'User'.
			?w :Contract ?p.
			?p rdf:type 'Operator'.
			?p :cf ?codicedue.			
         		                 }
	   )Calll

WHERE Calll.codice = Calll.codicedue
