Karel Appel is considered one of the most outstanding Dutch artists and one of the innovators of art after 1945: He was not only cofounder of the artists’ group CoBrA in 1948, but even after leaving the group developed a unique style, characterized by an unusual diversity. His works show bright colors, combined with imaginative and humorous elements of militant energy. On the one hand, the artist was inspired by primitive art and children's drawings, on the other hand, influences can be found from contemporaries such as Jean Dubuffet, the main representative of Art Brut. In addition to paintings, sculptures, reliefs, and canvases, he created numerous works on paper, which allowed Appel a special freedom in the development of motifs and gesture.