Two formation channels of ultra-compact dwarf galaxies in Hickson compact groupsC. Da Rocha, S. Mieske, I. Y. Georgiev, M. Hilker, B. L. Ziegler and C. Mendes de OliveiraA&A, 525 (2011) A86DOI: https://doi.org/10.1051/0004-6361/201015353