Tracing major structures of the inner Galaxy with 6.7-GHz methanol masers J.A. Green, J.L. Caswell, N.M. McClure-Griffiths, A. Avison, S.L. Breen, M.G. Burton, S.P. Ellingsen, G.A. Fuller, M.D. Gray, M. Pestalozzi et al. (2 more) EPJ Web of Conferences, 19 (2012) 06007 Published online: 07 February 2012 DOI: 10.1051/epjconf/20121906007