Variance shadow maps. - William Donnelly; Andrew Lauritzen (SI3D, 2006)

Layered variance shadow maps. - Andrew Lauritzen; Michael McCool (Graphics Interface, 2008)

Adaptive Volumetric Shadow Maps. - Marco Salvi; Kiril Vidimce; Andrew Lauritzen; Aaron E. Lefohn (Comput. Graph. Forum, 2010)

Sample distribution shadow maps. - Andrew Lauritzen; Marco Salvi; Aaron E. Lefohn (SI3D, 2011)