In the source article, you can read about the cases in which attempts were made to expose dubious paintings of Russian avant-garde without a credible provenance in France, Germany and Belgium with the intention to legalize them. These painting were allegedly by artists like Exter, El Lissitzky, Goncharova, Kandinsky, Malevich, Rodchenko and others. The way to the legalization, was supposed to be the Dieleghem Foundation from Brussels, founded by a Russian Igor Toporovski and his wife. Toporovski collaborated with Jean Chauvelin, the organizer of the exhibition "Alexandra Exter and her Russian friends", at chateau Tours in 2009. The vast majority of the paintings were counterfeits. The name Chauvelin has already appeared at the Czech art market in connection with the sale of František Kupka’s painting and in the connection with the exhibition of N. Goncharova at the Alšova Gallery in Hluboká in 2011. The effort to legalize the paintings is complemented by the effort to forge the catalogues to provide the provenance. At the end, one thought belongs to experts who confirm the authenticity of paintings.