Fast walkthroughs with image caches and ray casting. - Michael Wimmer 001; Markus Giegl; Dieter Schmalstieg (Comput. Graph., 1999)

Fitted virtual shadow maps. - Markus Giegl; Michael Wimmer 001 (Graphics Interface, 2007)

Queried virtual shadow maps. - Markus Giegl; Michael Wimmer 001 (SI3D, 2007)

Unpopping: Solving the Image-Space Blend Problem for Smooth Discrete LOD Transitions. - Markus Giegl; Michael Wimmer 001 (Comput. Graph. Forum, 2007)