@prefix ns: <http://example.com/ns/> .

[] a ns:Duck ;
    ns:duckCode "1" ;
    ns:d [
        a ns:Duck ;
        ns:duckCode "2" ;
        ns:d [
            a ns:Duck ;
            ns:duckCode "3" ;
            ns:d "cake" ;
        ] ;
    ] .
