Encarnação, José L. and Mengel, Maximilian and Bono, Peter R. and Böhm, Klaus and Borgmeier, Elmar and Brisson Lopes, J.M. and Hornung, Christoph and Knierriem-Jasnoch, Anette and Koch, Eckhard and Krömker, Detlef and Lindner, Rolf and Paris, Cesar and Sandberg, A. and Schnaider, Michael and Storck, Dietmar and Teixeira, José Carlos and Urban, Bodo and Wang, T. (1998):
A Concept and System Architecture for IT-Based Lifelong Learning.
In: Computers & Graphics, 22 (2-3), pp. 319-393. [Article]

Bono, Peter R. and Encarnação, José L. and Encarnação, L. Miguel and Herzner, Wolfgang R. (1990):
PC Graphics with GKS : Introduction to Graphics Standards (GKS, GKS-3D, PHIGS, CGI and CGM) and to Graphics Programming.
Prentice Hall, Hertfordshire, ISBN 0-13-654435-5,
[Book]