TY  - RPRT
TI  - RayGUI; a graphical user interface for interactive ray-tracing (rayinvr)
AU  - Jeremy Loss
AU  - I.A. Pecher
AU  - Uri S. ten Brink
PY  - 1998
DO  - 10.3133/ofr98203
UR  - https://pubs.usgs.gov/publication/ofr98203
ID  - ofr98203
ER  -