public static Set<RefOverridable> calculateSiblingReferences(RefMethod method) {
    final Set<RefOverridable> siblingReferences = new HashSet<>();
    final Stack<RefOverridable> pendingReferences = new Stack<>();
    pendingReferences.add(method);
    while (!pendingReferences.isEmpty()) {
      final RefOverridable referenceToAnalyze = pendingReferences.pop();
      siblingReferences.add(referenceToAnalyze);
      final Collection<? extends RefOverridable> overridingReferences = referenceToAnalyze.getDerivedReferences();
      for (RefOverridable overridingReference : overridingReferences) {
        if (!siblingReferences.contains(overridingReference) &&
            !pendingReferences.contains(overridingReference)) {
          pendingReferences.add(overridingReference);
        }
      }
      if (referenceToAnalyze instanceof RefMethod) {
        final Collection<RefMethod> superMethods = ((RefMethod)referenceToAnalyze).getSuperMethods();
        for (RefMethod superMethod : superMethods) {
          if (!siblingReferences.contains(superMethod) &&
              !pendingReferences.contains(superMethod)) {
            pendingReferences.add(superMethod);
          }
        }
      }

    }
    return siblingReferences;
  }
public static Set<RefOverridable> calculateSiblingReferences(RefMethod method)