In 1960, after only a year in business, Rudolf Zwirner’s fledgling gallery in Essen, Germany, was in serious debt. In a panic he turned to the dealer Hein Stünke, whose gallery in Cologne, Der ...

Rudolf Budja, a prominent art dealer known for his collection of Andy Warhols and more than 8,000 original prints of NASA’s space program dating back to the 1950s, has listed his eclectic ...