Takeo Igarashi Rieko Kadobayashi Kenji Mase Hidehiko Tanaka Path Drawing for 3D Walkthrough. 173-174 1998 ACM Symposium on User Interface Software and Technology http://doi.acm.org/10.1145/288392.288599 db/conf/uist/uist1998.html#IgarashiKMT98