iAd - configure app to serve ads in chosen countries

From the Apple’s Dev Center:

iAd Network Expansion and Updates

The iAd Network has recently launched in Canada,

Australia, and New Zealand. Ads are now available in apps in the U.S.,
Canada, Australia, New Zealand, Japan, France, Germany, Italy, Spain,
and the U.K App Stores.

_ Be sure to configure your apps to serve ads in only these countries. _

How can we do that ?

Is there a way in Corona to know the users country ?