Modern artists have extended the practice of painting considerably to include, for example, collage. This began with cubism and is not painting in strict sense. Some modern painters incorporate different materials such as sand, cement, straw or wood for their texture. Examples of this are the works of Jean Dubuffet or Anselm Kiefer. Modern and contemporary art has moved away from the historic value of craft in favour of concept; this has led some to say that painting, as a serious art form, is dead, although this has not deterred the majority of artists from continuing to practise it either as whole or part of their work.