A return ticket is often requested, but enforcement varies; a ticket to a third country (e.g., Brazil) can be accepted. Some travelers have successfully entered without return tickets or hotel bookings, but this is not guaranteed. A yellow fever vaccination certificate is generally NOT required if staying only in Buenos Aires. However, for travel to other regions within Argentina or certain neighboring countries, it might be mandatory. Hotel bookings, especially pre-paid ones, can be important for entry, as observed for Mexico.
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