It depends on how the tracking is configed.
Option A: If the tracking code for the Analytics property is only added to pages within that section, then the answers would be:
The referrer would be the top level domain for the site.
Because as far as that Analytics property is, that directory is the website and traffic from outside is not from the website.
Option B: If the tracking code is the same for the rest of the site, and the view is merely filtered to just show data for that directory:
The referrer would be the original referrer for that user session.
This is because Analytics still sees the rest of the site, but it will only give you information for pageviews within that directory.
To be honest, option B possibly isn't the set up you want to work with as it doesn't help you if that directory is your sole concern. You might want to speak to the webmaster to have a new Analytics property set up for just that directory.