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I am visiting my sister in Switzerland, my visa type C, my duration of stay 32 days for 30/Aug to 1/Oct.
I want to extend my stay 10 days more, is it possible? And if I can, where should I go to? (it's still 7 days in my visa visit it end at 1/Oct i want to stay to 11/Oct ). What can I do? And what documents I need?
Could anyone please suggest if I would need a formal approval process from local canton office?

marked as duplicate by Mark Mayo, jpatokal, JoErNanO, Karlson, Danubian Sailor Jan 9 '15 at 7:41

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