© Artists Rights Society (ARS), New York/VG Bild-Kunst, Bonn Luftpost Joseph Beuys Accession Date: 05/01/06 Accession Number: F-BEUYS-106.029 1971 airmail envelope with page from a chemistry textbook; with several stamps 4 1/2 x 6 3/8 in. (11.43 x 16.19 cm)