(OB-737) Serigraph #23 in "The Angles of Open Form Infinite Space from Cinètisme to Open Form 1949 - 1968" Edited in 1968 in New York, Paris and Stockholm. Edition limited to 300 albums. Each serigraph numbered 1 to 300, signed by Baertling. L-4 sign 5 st, L-G sts 4st.
