Esther Hoorn Maurits van der Graaf Corporation for National Research Initiatives February 2006 article 10.1045/february2006-vandergraaf http://www.dlib.org/dlib/february06/vandergraaf/02vandergraaf.html English D-Lib Magazine 1082-9873 12 2 Copyright Esther Hoorn and Maurits van der Graaf