Yoko Ono, FROM MY WINDOW: Salem 1692, 2002, pigment on canvas, private collection/ （ｃ）YOKO ONO 2015

Yoko Ono, Invisible Flower, 1952, ink and pastel on paper, private collection/ （ｃ）YOKO ONO 2015

Yoko Ono, Invisible Flower, 1952, ink and pastel on paper, private collection/ （ｃ）YOKO ONO 2015

Yoko Ono, Cloud Peace, 1963/2005, Sky TV for Hokkaido, part of the permanent exhibition at Tokachi Millennium Forest. Cloud Peace instructions: "Imagine clouds dripping down. Dig a hole in your garden to hold the clouds." Spring 1963/ （ｃ）YOKO ONO 2015

Yoko Ono, Hole, 2009, bullet-pierced glass plate, engraved text "Go around to the other side of the glass and look through the hole", metal frame (partial), private collection/ （ｃ）YOKO ONO 2015

Yoko Ono, Chair Piece, 1962, performed at the "John Cage and David Tudor Event" (Kyoto Kaikan, October 12, 1962). Photo: Yasuhiro Yoshioka, Private Collection, Courtesy of Lenono Photo Archive/ （ｃ）YOKO ONO 2015

Yoko Ono, Vertical Memory, 1997, 22 framed iris prints, text and photography by Colin Davison, private collection/ （ｃ）YOKO ONO 2015

Yoko Ono, "Pictures Assembled in My Head, Part 1," Spring 1962, type and ink on postcard, private collection. A square canvas is transformed in my mind until it becomes a circle. At a certain point in the process, I stop and stretch on the canvas a color,/ （ｃ）YOKO ONO 2015