On the distance to the North Polar Spur and the local CO-H2 factor R. Lallement, S. Snowden, K. D. Kuntz, T. M. Dame, D. Koutroumpa, I. Grenier and J. M. Casandjian A&A, 595 (2016) A131 Published online: 17 November 2016 DOI: 10.1051/0004-6361/201629453