Summer auction at Ketterer Kunst to offer works by Ilona Singer and Hans Thoma Hans Thoma, Flora, 1882. Oil on paper, 113 x 62 cm / 44.4 x 24.4 in. Estimate: 25,000-35,000 / US$ 28,750-40,250. MUNICH .- Two works by Ilona Singer and Hans Thoma have both notable provenances and a fascinating history in common. On top they also represent best practice when it comes to finding solutions for works of looted art. Now these two rediscoveries will be sold in the Summer Auction at Ketterer Kunst in Munich on June 18/19. Unfortunately, large scale rehabilitation of loss of Jewish property attributed to prosecution still is no matter of course. And this is where I see the art trade bearing responsibility. We must not leave owners of such difficult works alone with their problems, says company owner Robert Ketterer. We have to deploy all our competence to find solutions. Which is why I am all the happier that we were able to identify the true heirs and that we could help to mediate between them and the consignors. This way we made these two artworks marketable again in the sense of a fair and juts solution.