code: @Override
      public void addDisjointObjectPropertiesAxiom(ObjectPropertyExpression... opes) throws InconsistentOntologyException {
          for (ObjectPropertyExpression p : opes)
              checkSignature(p);
          objectPropertyAxioms.addDisjointness(opes);
      }
docs: Normalizes and adds object property disjointness axiom
  <p>
  DisjointObjectProperties := 'DisjointObjectProperties' '(' axiomAnnotations
  ObjectPropertyExpression ObjectPropertyExpression { ObjectPropertyExpression } ')'<br>
  <p>
  Implements rule [O2]:<br>
  - eliminates all occurrences of bot and if the result contains<br>
  - no top and at least two elements then disjointness<br>
  - one top then emptiness of all other elements<br>
  - two tops then inconsistency (this behavior is an extension of OWL 2, where duplicates are removed from the list)