Calibration of TRACE Lyman-α images using SOHO/SUMER observations Sungsoo S. Kim, Hee-Seon Roh, Kyung-Seok Cho and Junho Shin A&A, 456 2 (2006) 747-750 Published online: 31 August 2006 DOI: 10.1051/0004-6361:20054714