Ruhrberg, K., & Walther, I. F. (2005). Art of the 20th century. Taschen.
Cita Chicago Style (17a ed.)Ruhrberg, Karl, y Ingo F. Walther. Art of the 20th Century. Hongkong: Taschen, 2005.
Cita MLA (9a ed.)Ruhrberg, Karl, y Ingo F. Walther. Art of the 20th Century. Taschen, 2005.
Precaución: Estas citas no son 100% exactas.