/// <exception cref="W3c.Ddr.Exceptions.NameException">Thrown when...</exception>
 public IPropertyRef NewPropertyRef(IPropertyName pn)
 {
     VocabularyProperty vocabularyProperty = vocabularyHolder.ExistProperty(pn.LocalPropertyName(), null, pn.Namespace(), true);
     return NewPropertyRef(pn, vocabularyProperty.defaultAspect);
 }
 /// <exception cref="W3c.Ddr.Exceptions.NameException">Thrown when...</exception>
 public IPropertyRef NewPropertyRef(IPropertyName pn, string localAspectName)
 {
     vocabularyHolder.ExistProperty(pn.LocalPropertyName(), localAspectName, pn.Namespace(), true);
     return new ODDRPropertyRef(pn, localAspectName);
 }