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A better copy of this painting, not in Ertz, is in Schloss Grunewald, cat. #2548 (copper, 45 x 63) -- wiki page. It was possibly in Potsdam by 1698. Photo of a much worse version at RKD as sold Brussels (Barbiers) 12/6 1912 #20.
Variant sold Barbier sale, S. Gudule, Brussels, June 12-13, 1912, #20 (panel, 52 x 67 cm)