[CII] observations of H2 molecular layers in transition clouds T. Velusamy, W. D. Langer, J. L. Pineda, P. F. Goldsmith, D. Li and H. W. Yorke A&A, 521 (2010) L18 Published online: 01 October 2010 DOI: 10.1051/0004-6361/201015091