Keen, G. (1971). The sale of works of art: A study based on the Times-Sotheby Index. Nelson.
Chicago-referens (17:e uppl.)Keen, Geraldine. The Sale of Works of Art: A Study Based on the Times-Sotheby Index. [London]: Nelson, 1971.
MLA-referens (9:e uppl.)Keen, Geraldine. The Sale of Works of Art: A Study Based on the Times-Sotheby Index. Nelson, 1971.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.