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G. Vega-gorgojo, He is currently studying towards a PhD degree in telecommunications engineering at the University of Valladolid. He is a Teaching Assistant at the Department of Signal Theory His research interests include semantic web and grid technologies to support CSCL systems, 2000.

M. Luis-bote, He is a Teaching Assistant at the Department of Signal Theory His research interests include CSCL systems and grid computing. Eduardo Gómez-Sánchez received the M.S. and the PhD degrees in telecommunications engineering from University of Valladolid, Spain, in 1996 and 2001, respectively. He is currently an Associate Professor at the Department of Signal Theory His research interests include distributed systems and their application to the design and implementation of CSCL scenarios. Yannis A. Dimitriadis received the engineering degree from the National Technical University of Athens, and the PhD degrees in telecommunications engineering from the M.S. from the University of Virginia (1983) and two PhD degrees from the University of His research interests include computer supported collaborative learning and distributed systems, 1981.