FOCES - a fibre optics Cassegrain échelle spectrograph M. J. Pfeiffer, C. Frank, D. Baumüller, K. Fuhrmann and T. Gehren Astron. Astrophys. Suppl. Ser., 130 2 (1998) 381-393 Published online: 15 June 1998 DOI: 10.1051/aas:1998231