Open Form - Recommended reading:

Oskar Hansen: "Towards Open Form" [ISBN 83-89302-07-1]

Oskar Hansen: "Zobaczyc Swiat" [ISBN 83-89145-70-7 & 83-87321-78-8]

Documenta Magazine: "Part 1 of the series 'Games, Visual Conversations, Activities and Interactions"

Documenta Magazine: "Part 4 of the series 'Games, Visual Conversations, Activities and Interactions"

Polish Culture: Oskar Nikolai Hansen: http://www.culture.pl/en/culture/artykuly/os_hansen_oskar

Oskar Hansen and the Auschwitz "Countermemorial," 1958-59: http://web.archive.org/web/20070614162550/http://www.artmargins.com/content/feature/murwaska.html