1. The ZEUS Detector, Status Report 1993, DESY 1993.
2. A Microvertex Detector for ZEUS, ZEUS Collaboration, DESY-PRC 97/01.
3. Helix128-2.x User Manual, Wolfgang Fallot-Burghardt et al., HD-ASIC-33-0697. The modifications for ZEUS (HELIX 3.0) are described in http://wwwasic.ihep.uni-heidelberg.de/ ̃feuersta/projects/Helix/index.html.
4. M.D.M. de Fez Laso et al., Proceedings of 2nd Workshop on Electronics for LHC Experiments, CERN/LHCC/96-39, 1996, p. 499.