Hi there,

       The two following references seem to have broken links
Seismic Sensors and Their Calibration. Overview of feedback seismometers 
design by Prof. Erhard Wielandt. 
Seismometry another article by Prof. Erhard Wielandt. 

       They can be recovered from 
http://www.geophys.uni-stuttgart.de/lehre/skripte/old_skripte/old_skripte.html

       Regards,

       Chris Chapman
Hi ther=
e,



       The two following references seem to ha=
ve broken links

Seismic Sensors and Their Calibration. Overview of feedback seismome=
ters design by Prof. Erhard Wielandt. 

Seismometry another article by Prof. Erhard Wielandt. 



       They can be recovered from http://www.g=
eophys.uni-stuttgart.de/lehre/skripte/old_skripte/old_skripte.html



       Regards,



       Chris Chapman