Guston, Philip. Untitled, (1967, ink on paper, 44.5 x 57 cm). Sourced from http://arthistory.about.com/od/from_exhibitions/ig/guston_works_on_paper/guston_mlm_06.htm

Adorno, Theodor. Negative Dialectics, trans. E.B.Ashton, (Continuum, New York, 2005) , p.191.

VERSUCH image from Presentation, Not Representation 2010