This diagram shows a "flattened" representation of an entry, where attributes defined in ExtensionModules are first-class attributes of the entry itself -- instead of being "referenced by" or "linked to" an entry, they are actual attributes of Entry.
content and BiblioGraphy show a container relationship with Entry, where the entry can have zero, one, or more of groups of related attributes.
This style of model is characteristic of AssociativeDataModels, dynamic languages, and XML, in contrast to RelationalDataModels and static languages. See also dynamic and static languages.
Here's a one page comparison of data models.
now rewritten, is it clearer?
Yes, thanks. You're pointing out that the entry has a number of attributes that it "owns" and a number of other attributes that hold relations to other entities.
content multiple parts of the content?
BiblioGraphy various versions of the content? Is this the same as AlternativeRepresentation?
Related other entries citing or cited by the entry
See discussion at SiteAndSyndication about an entry's relations to containers