<hi xmlns="http://www.tei-c.org/ns/1.0" rend="bold" style="font-family:Open Sans">Wilkinson, Leland</hi><hi xmlns="http://www.tei-c.org/ns/1.0" style="font-family:Open Sans" xml:space="preserve"> (2005): </hi><hi xmlns="http://www.tei-c.org/ns/1.0" rend="italic" style="font-family:Open Sans">The grammar of graphics</hi><hi xmlns="http://www.tei-c.org/ns/1.0" style="font-family:Open Sans">. 2. Aufl. New York: Springer.</hi>