Borys, Bernd-Burkhard, Sundström, G. A., Fejes, Lajos, Strätz, Gerd The intelligent graphical editor with design support and user model (IGE3): ESPRIT-GRADIENT Report P857-WP11-UKS 059, Bd. 10: IMAT-Bericht / MMS, Kassel 1990.

Borys, Bernd-Burkhard, Sundström, G. A., Fejes, Lajos, Strätz, Gerd The intelligent graphical editor with design support and user model (IGE3): ESPRIT-GRADIENT Report P857-WP11-UKS 059, Bd. 10: IMAT-Bericht / MMS, Kassel 1990.