"Artikle 9
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b) Each contracting State reserves also the right, in exceptional circumstances or during a period of emergency, or in the interest of public safety, and with immediate effect, temporarily to restrict or prohibit flying over the whole or any part of its territory, on condition that such restriction or prohibition shall be applicable without distinction of nationality to aircraft of all other States.
c) Each contracting State, under such regulations as it may require any aircraft entering the areas contemplated in subparagraphs a) or b) above to effect a landing as soon as practicable thereafter at some designated airport within its territory."