Helmut Degen Ein Wirkmodell für eine marktorientierte Konzeption und Produktion von Softwareprodukten. [Citation Graph (0, 0)][DBLP] Software-Ergonomie, 1999, pp:389-390 [Conf]
Helmut Degen Performance Model for Market-Oriented Design of Software Products. [Citation Graph (0, 0)][DBLP] Int. J. Hum. Comput. Interaction, 2000, v:12, n:3-4, pp:285-307 [Journal]
Helmut Degen Book Review: User Interfaces for All: Concepts, Methods, and Tools by C. Stephanidis (Ed.). [Citation Graph (0, 0)][DBLP] Int. J. Hum. Comput. Interaction, 2003, v:16, n:3, pp:515-516 [Journal]