(1980). Projects: Richard Long, Joseph Beuys, Dan Graham. Artforum.
Cita Chicago (17th ed.)"Projects: Richard Long, Joseph Beuys, Dan Graham." Artforum 1980.
Cita MLA (8th ed.)"Projects: Richard Long, Joseph Beuys, Dan Graham." Artforum, 1980.
Atenció: Aquestes cites poden no estar 100% correctes.