Knox is on the promotion trail for "Waiting to be Heard," her memoir about being imprisoned for four years in Italy for a murder she says she did not commit.
Knox, 25, was convicted in December 2009 after two years in prison and sentenced to 26 years for the stabbing death of her British roommate, Meredith Kercher.
Two years later, her conviction was overturned on appeal, but Italy's Supreme Court recently decided she must be tried again.
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