* Verifies that the {@code Set} returned by {@code incidentEdges} has the expected mutability
   * property (see the {@code Network} documentation for more information).
   */
  @Test
  public abstract void incidentEdges_checkReturnedSetMutability();

  /**
   * Verifies that the {@code Set} returned by {@code adjacentNodes} has the expected mutability
   * property (see the {@code Network} documentation for more information).
   */
  @Test