An art installation formed with milk churns, made by land art artist Gerard Benoit a la Guillaume, is seen at the Chenau de Mayen in the resort of Leysin, Switzerland August 7, 2015. More than 80 milk churns were placed between the Tour d'Ai and the Tour de Mayen summits at an altitude of 2,000 meters (6,561 feet) above sea level under the direction of the artist, to be photographed for his ongoing art project entitled “Milk churns without borders”. (Photo by Denis Balibouse/Reuters)

Gold bars from the vault of a bank and Swiss one franc coins are seen in this illustration picture taken in Zurich November 20, 2014. The “Save our Swiss gold” proposal, spearheaded by the right-wing Swiss People's Party (SVP), aims to ban the central bank from offloading its reserves and oblige it to hold at least 20 percent of its assets in gold. The referendum is scheduled for November 30. The SVP argues it would secure a stable Swiss franc. (Photo by Arnd Wiegmann/Reuters)

Two young women pose for a portrait, dressed in robes after collecting their Bachelor degrees in Conakry on October 12, 2020. Presidential elections are to be held on October 18, with incumbent President bidding for a third term in office, defying critics who say he forced through a new constitution this year enabling him to sidestep two-term presidential limits. (Photo by John Wessels/AFP Photo)

Clutching a large paper bag and shading his eyes as he peers ahead, comic actor of the silent screen, Buster Keaton (1885–1966) arriving at Paris airport. (Photo by Keystone/Getty Images). 1st August 1947

Members of the Communist New Fourth Army on parade. Note how the modern equipment contrasts with the shoeless soldiers in the foreground. (Photo by Hulton Archive/Getty Images). 6th July 1946

A high-kicking Parisian can-can dancer. (Photo by Hulton Archive/Getty Images). 1895

A child working at Ship breaking yard in Chittagong, Bangladesh on November 14, 2014. (Photo by Pascal Mannaerts/Alamy Stock Photo)