NASA http://dragon.larc.nasa.gov/retinex/
E.B.: Erwin Blumenfeld, Copyright (C) The Estate of Erwin Blumenfeld
E.B.: Erwin Blumenfeld, Copyright (C) The Estate of Erwin Blumenfeld
E.B.: Erwin Blumenfeld, Copyright (C) The Estate of Erwin Blumenfeld
E.B.: Erwin Blumenfeld, Copyright (C) The Estate of Erwin Blumenfeld
Photograph courtesy Philip Greenspun (http://philip.greenspun.com)
John D. Willson, USGS Amphibian Research and Monitoring Initiative
Ken Stansell, U.S. Fish and Wildlife Service
CC by Juan Gabriel Gomila
Kobus Barnard, SFU Computational Vision Laboratory (http://www.cs.sfu.ca/~colour/data/)