Anisotropic dynamic response of pentacene single crystals R. Schuster, M. Knupfer, D. R.T. Zahn and H. Berger Eur. Phys. J. B, 59 1 (2007) 25-28 Published online: 28 September 2007 DOI: 10.1140/epjb/e2007-00256-6