S. Card, G. Robertson, und J. Mackinlay. ACM SIGCHI?91 Conference on Human Factors in Computing Systems, Seite 181--188. New Orleans Louisiana, ACM, (1991)
J. Cugini, S. Laskowski, und M. Sebrechts. IST/SPIE's 12th Annual International Symposium: Electronic Imaging 2000: Visual Data Exploration and Analysis (SPIE 2000), San Jose, CA, (2000)