A complete 12CO 2–1 map of M 51 with HERA - II. Total gas surface densities and gravitational stabilityM. Hitschfeld, C. Kramer, K. F. Schuster, S. Garcia-Burillo and J. StutzkiA&A, 495 3 (2009) 795-806DOI: https://doi.org/10.1051/0004-6361:200810898
