Georges Braque of monochromatic color and complex patterns of faceted form, now termed Analytic Cubism. A decisive time of its development occurred during the summer of 1911, when Georges Braque and Pablo Picasso painted side by side in Céret in the French Pyrenees, each artist producing paintings that are difficult—sometimes virtually impossible—to distinguish from those of the other. In 1912, they began to experiment with collage and Braque invented the "papier collé" technique. On 14 November 1908, the French art critic Louis Vauxcelles, in his review of Georges Braque's exhibition at Kanhweiler's gallery called Braque a daring man who despises form, "reducing
20th-century Western painting for that spiritual knowledge. Other major pioneers of early abstraction include Swedish painter Hilma af Klint, Russian painter Kazimir Malevich, and Swiss painter Paul Klee. Robert Delaunay was a French artist who is associated with Orphism, (reminiscent of a link between pure abstraction and cubism). His later works were more abstract, reminiscent of Paul Klee. His key contributions to abstract painting refer to his bold use of color, and a clear love of experimentation of both depth and tone. At the invitation of Kandinsky, Delaunay and his wife the artist Sonia Delaunay, joined The Blue Rider (Der Blaue Reiter), a