Navigation and Interaction in a Multi-Scale Stereoscopic Environment. - Ernst Houtgast; Onno Pfeiffer; Zachary Wartell; William Ribarsky; Frits H. Post (VR, 2005)

Interaction Volume Management in a Multi-scale Virtual Environment. - Zachary Wartell; Ernst Houtgast; Onno Pfeiffer; Christopher D. Shaw; William Ribarsky; Frits H. Post (Advances in Information and Intelligent Systems, 2009)