(Imported from Google Code)
DDMSence maintains a link from producer entities and country codes to the component that contains them (producers for entities, and geographicIdentifier/postalAddress for countryCodes).
This makes the object hierarchy more rigid, and only helps when outputting HTML/Text output. Eliminating this parentType would clean up the code quite a bit. Without it, it would be the responsibility of the parent item to deal with the output of its children.