Armando Museum # CONSTANT/PERMEKE # 2004, signed, mint
Benno Wissing # Museum Boymans van Beuningen # CONSTANT / PERMEKE # 1958, B--
Bibliotheque d'Alexandrie Paris # CONSTANT # 1959, NM+++/Mint--
Constant # NEW BABYLON, Art et Utopie# 1997, mint
G.I.N. gallery # CONSTANT # 1979, mint--
Haags Gemeentemuseum # CONSTANT, New Babylon # poster,1974, B--
Witte de With # #1 FROM WITTE DE WITH , incl New Babylon # 1999, mint