Underbrace cannot be used inside an equation in the form: [Latex code] \underbrace{somexpression}_{someexpression} You cannot put anything under the ``underbrace command'' isn't this a bug? However if somebody modify the latex code and imports it, everything seems all right in the screen, but you can't modify anything under the brace. -- TITO LÓPEZ CIUDAD E-Mail: [EMAIL PROTECTED] Instituto de Ciencias de Materiales de Madrid (CSIC) Campus Cantoblanco E-28049 Madrid. Tel. +34-91-334-90-00 Ext 130 Tel. +34-91-372-14-20 Ext 130 FAX: +34 91 3720623