"Flemish School" is by Hans Rottenhammer

Thiollet, from France, sells on 10 October 2017 a "Flemish School" Dancing putti, a small oil on copper (29 by 36 cm) estimated at 2000 to 3000 Euro.

The work is probably by Hans Rottenhammer, after a Jan Brueghel composition.

The Brueghel is from the Alte Pinakothek, and dates to ca. 1605.

Another versions by Rottenhammer can be found in the Museum of La Valletta, in Malta.

A nearly identical, though perhaps somewhat better painted version was sold at Christie's in 2009 for £31,000, indicating that the one for sale now is probably seriously undervalued and should fetch 10,000 Euro instead, although it needs some cleaning or restoration.(larger image found through RKD).

UPDATE: now for sale at Jean Moust for 7,000€ as by Rottenhammer, seems a very reasonable price.