FILE - In this Thursday, Nov. 2, 2017 file photo, a visitor enters the exhibition 'Gurlitt : Status Report' at the Bundeskunsthalle museum in Bonn, Germany. German authorities say they have have now returned all 14 works from the art trove, accumulated by late collector Cornelius Gurlitt and so far were proven to have been looted under Nazi rule, to their heirs. (AP Photo/Martin Meissner, file)BERLIN – German authorities have now handed over all 14 works from the art trove accumulated by late collector Cornelius Gurlitt that so far were proven to have been looted under Nazi rule, the government said Wednesday. The following year, it was bought by Gurlitt's father, Hildebrand Gurlitt — an art dealer who traded in works confiscated by the Nazis. A trickle of works has been handed back in recent years as the painstaking process of provenance research made gradual progress.