=========================================== Extinct Components or Intentionally Omitted =========================================== This section acknowledges and gives reasoning for classes or properties that were intentionally left out. This can be revisited or changed if necessary. ------------------ pcdmworks:TopRange ------------------ The `PCDM Works Extension `_ defines a class :code:`pcdmworks:TopRange` that is meant to be the parent Range in a book. This was due to requirements for the IIIF Presentation API prior to version 3 where the top most range in a sequence needed a :code:`viewingHint="top"` property. Since version three, this is no longer required and complex hierarchy can be modelled simply with the :code:`pcdmworks:Range` class and properties and classes from :code:`iana` and :code:`ore`. ----------- pcdm:Object ----------- The :code:`pcdm:Object` class is extended by other subclasses that add much more flexibility. For now, :code:`pcdm:Object` has been dropped in lieu of its subclasses.