Authors: Jang-Ung Park; Matt Hardy; Seong Jun Kang; Kira Barton; Kurt Adair; Deep Kishore Mukhopadhyay; Chang Young Lee; Michael S Strano; Andrew G Alleyne; John G Georgiadis; Placid M Ferreira; John A Rogers Journal: Nat Mater Date: 2007-08-05 Impact factor: 43.841