Planck Collaboration, Ade, P. A. R., Aghanim, N., Arnaud, M., Ashdown, M., Aumont, J., et al. (2011). Planck early results - XXIII. The first all-sky survey of galactic cold clumps. Astronomy & Astrophysics, 536: A23, pp. 1-33. doi:10.1051/0004-6361/201116472.