September 1971 issue of the German art periodical Interfunktionen. With contributions by Joseph Beuys, Richard Long, Michael Heizer, Dennis Oppenheim, Peter Hutchinson, Robert Smithson, Buckminster Fuller, Nam June Paik, Dan Graham, Lotar Baumgarten, Will Insley, Jürgen Kramer, and Panamarenko. Edited by Friedrich Wolfram Heubach. Printed in black-and-white. Text in German and English.