6. ACKNOWLEDGMENT 
This work is implemented in the framework of the Euro- 
pean Telematics Applications Program project PRONET 
ET-1017. The authors would like to thank all project part- 
ners for their contribution to the project. 
7. REFERENCES 
PRONET — Multimedia Computer Based On-Line Training 
and Support Service for Professionals. Telematics Edu- 
cation & Training Programme, ET-1017, Project Pro- 
gramme, European Commission, 1995. 
http://WWW.eurocom.intranet.gr/EurPrj/pronet/ 
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