BIBCYT http://bibcyt.ucla.edu.ve/cgi-win/be_alex.exe?Ultimo&Nombrebd=BIBCYT UCLA - Biblioteca de Ciencias y Tecnologia Felix Morales Bueno Hoffman, Donna L donna.hoffman@vanderbilt.edu P Principal Venkatesh , Alladi avenkate@uci.edu P Principal Novak , Thomas P. Tom.Novak@owen.vanderbilt.edu P Principal Communications of the ACM Vol: 47 pp.37-42; 28 cm.; il.