In Civilization 5, can I burn a city state which has joined Austria by marriage?

In Civ 5, I know that I can't burn a capital or a city state. However, does this restriction apply to city states which have joined Austria through their unique ability, Diplomatic Marriage?

I would test it myself but I can't as my computer is currently hosting a long term pitboss game, and I need to know the answer to inform my decisions in that game.

Solution 1:

If Austria gains a city state via diplomatic marriage, it's no longer considered a city state - it counts as one of their cities instead. Thus, it can be burned, and cannot be liberated.

The same is true of city states bought by Venice.