- Robert Barry: 30 pieces as of 14 June 1971
- Gerd de Vries, 1971
- soft cover
- edition 1000
- Ask
- Robert Barry: 30 pieces as of 14 June 1971
- Gerd de Vries, 1971
- soft cover
- edition 1000
- Ask
Something which is very near in place and time, but not yet known to me
contexts：
- Art As Idea As Idea 1967-1968
- Joseph Kosuth
- Paul Maenz, Brussels, 1973 ⁄ softcover
- Ask
- Paul Maenz Jahresbericht 1971
- Paul Maenz
- Paul Maenz, Koln, 1971 ⁄ softcover
- Ask
- Prospect 71 Projection
- Konrad Fischer / Jürgen Harten / Hans Strelow
- Art-Press Verlag, 1971 ⁄ soft cover
- Ask
- Salon nr.6, Januar 1979
- Gerhard Theewen
- Salon Verlag, 1979 ⁄ softcover
- Ask