@Test
public void testAuthorship() throws Exception {

  Authorship auth = new Authorship();
  assertNull(auth.toString());
  
  auth.setAuthors(Lists.newArrayList("L."));
  assertEquals("L.", auth.toString());
  
  auth.getAuthors().add("Rohe");
  assertEquals("L. & Rohe", auth.toString());
  
  auth.getAuthors().clear();
  auth.setYear("1878");
  assertEquals("1878", auth.toString());
  
  auth.getAuthors().add("L.");
  auth.getAuthors().add("Rohe");
  assertEquals("L. & Rohe, 1878", auth.toString());
  
  auth.setExAuthors(Lists.newArrayList("Bassier"));
  assertEquals("Bassier ex L. & Rohe, 1878", auth.toString());
}