Are PAHs precursors of small hydrocarbons in photo-dissociation regions? The Horsehead case J. Pety, D. Teyssier, D. Fossé, M. Gerin, E. Roueff, A. Abergel, E. Habart and J. Cernicharo A&A, 435 3 (2005) 885-899 Published online: 13 May 2005 DOI: 10.1051/0004-6361:20041170