Mark Tobey (American, 1890-1976) 2 plates from the suite Six Impromptus on Omar KhayyamI. 1971. Aquatint. Each sheet280x265mm. Printed in color. Very fine proofs on vellum, numbered, signed and dated in pencil. Full margins. Edition of 75 proofs. Dry stamp: Edition de Beauclair, Frankfurt-am-Main. Framed (not examined out of frame). Set. 2 p.