Copy sold Stockholm (Stockholms Auktionsverk, May 16, 2000, #1434) as circle of Jan the Younger (copper, 48 x 70); copy sold New York (Christie's, May 31 1990, #115) as Jan the Younger (copper, 48.5 x 64). wiki pages for both. the latter was catalogued by Ertz as Jan the Younger, 1984 #242.
Copy sold Szapary sale, Ernst-Museum, Budapest, April 29, 1929, #73 (panel, 64 x 108 cm)
This is by far the better painting at this museum. It is less densely painted and a great deal of the ground layer is visible: you can see a lot of process really clearly. Rubens must have done his part first but also he did parts of ground, including trees, because the figures are completely integrated in terms of poses, shadowing and so forth. The putto/dogs interaction is also nice and unusual and argues for a good "understanding" between the two players. In some of the dogs you can clearly see the way Jan first drew a sketch form--some are not even really filled in.
Interesting comparison on how Rubens integrates a figure group (the sleeping nymphs) vs. how Brueghel does it with the dogs. Dogs are much more indivuated, linear, cut-outs juxtaposed against one another, at best puzzle pieces. Rubens's figures are a mass in which individuals emerge and then remerge. Note how women are particularly treated like this.
In great condition.
Freedberg, in his review of Ertz, doubted that Rubens did the figures here.