UNIVERSITY OF HUDDERSFIELD, UNITED KINGDOM.
ARISTOTLES UNIVERSITY OF THESSALONIKI, GREECE.
POLITEHNICA UNIVERSITY OF BUCHAREST.
TECHNICAL UNIVERSITY SOFIA.
PRINCETON UNIVERSITY, USA.
PURDUE UNIVERSITY, USA.
SAN DIEGO STATE UNIVERSITY, USA.
OHIO STATE UNIVERSITY, USA.
TEXAS A&M UNIVERSITY, USA.
FEDERAL UNIVERSITY OF CAMPINA GRANDE, ITALY.
MY DEFENCE, DENMARK.
SINGULAR LOGIC, GREECE.
GREEK TELECOM ORGANISATION, GREECE.
SOFIA TECH PARK JSC, BULGARIA.