Comella CL, Jankovic J, Truong DD, Hanschmann A, Grafe S. Efficacy and safety of incobotulinumtoxinA (NT 201, XEOMIN®, botulinum neurotoxin type A, without accessory proteins) in patients with cervical dystonia. J Neurol Sci. 2011 Sep 15; 308(1-2):103-9.