CAMPUS: a simulative, flexible, case-oriented web-based training system for multi-purpose use in PBL-curricula - Riedel, Jens; Singer, R.; Heid, Jörn; Leven, Franz-Josef; Schnabel, K.; Tönshoff, Burkhard; Köpf, S.; Jünger, Jana (Multimedia in health sciences education, 2001)