Luigi Ghirri, Lucerna, From the series Fotografie del periodo iniziale, 1972. Vintage c-print, 2 3/8 x 4 inches; 6 x 10 cm. On view at Matthew Marks Gallery in Los Angeles until June 21.

Sterling Ruby, ACTS/SOME RISE SOME REST, 2014,. Clear urethane block, dye, wood, and formica
, 65 3/4 x 112 x 35 1/4 in
. Urethane Block: 30 x 72 x 7 in
. Pedestal: 35 x 84 x 35 in. On view at Hauser & Wirth in New York until July 25.

Bridget Riley, Installation view, "The Stripe Paintings 1961-2014." On view at David Zwirner in London until July 25.

Gerhard Richter, WALD (FOREST), 2005. Oil on canvas, 197 x 132 cm. On view at the Fondation Beyeler in Basel, Switzerland until September 7.