Armstrong, Helen (2009). Graphic Design Theory: Readings From The Field. New York, NY, USA: Princeton Architectural Press. pp. 110–137. ISBN978-1-56898-772-9. LCCN2008021063. OL16865234M.
Armstrong, Helen (2009). Graphic Design Theory: Readings From The Field. New York, NY, USA: Princeton Architectural Press. pp. 110–137. ISBN978-1-56898-772-9. LCCN2008021063. OL16865234M.