Kinematic structure of massive star-forming regions - I. Accretion along filaments J. Tackenberg, H. Beuther, Th. Henning, H. Linz, T. Sakai, S. E. Ragan, O. Krause, M. Nielbock, M. Hennemann, J. Pitann and A. Schmiedeke A&A, 565 (2014) A101 Published online: 19 May 2014 DOI: 10.1051/0004-6361/201321555