High-mass star formation at high luminosities: W31 at >106 L⊙ H. Beuther, H. Linz, Th. Henning, A. Bik, F. Wyrowski, F. Schuller, P. Schilke, S. Thorwirth and K.-T. Kim A&A, 531 (2011) A26 Published online: 06 June 2011 DOI: 10.1051/0004-6361/201116686