@Test
 public void getIRI_shouldReturnAnIRIThatStartsWithSkosPrefix() {
   assertThat(vocabulary.getIRI().toString(), startsWith(Namespaces.SKOS.getPrefixIRI()));
 }
 @Test
 public void getPrefixedName_shouldStartWithSkosPrefixName() {
   assertThat(vocabulary.getPrefixedName(), startsWith(Namespaces.SKOS.getPrefixName()));
 }