1. Blattner M, Sumikawa D, Greenberg R (1989) Earcons and icons: their structure and common design principles. Hum-Comput Interact 4:11–44
2. Bowman D, Kruijff E, La Viola J, Poupyrev I (2000) The art and science of 3D interaction. Tutorial notes from the IEEE International Virtual Reality 2000 conference. New Brunswick, NJ, March 18–22
3. Brewster SA, Wright PC, Edwards ADN (1993) An evaluation of earcons for use in auditory human–computer interfaces. In: Ashlund S, Mullet K, Henderson A, Hollnagel E, White T (eds) Proceedings of InterCHI‘93. ACM, Amsterdam, pp 222–227
4. Brewster SA, Wright PC, Edwards ADN (1994) The design and evaluation of an auditory-enhanced scrollbar. In: Adelson B, Dumais S, Olson J (eds) Proc. of CHI‘94. ACM, Boston, MA, pp 173–179
5. Chen JL, Stanney KM (1999) A theoretical model of wayfinding in virtual environments: proposed strategies for navigational aiding. Presence: Teleoperators and Virtual Environments 8(6):671–685