Ries Al & Trout, J. (2001). Positioning: The battle for your mind (20th anniversary edition.). McGraw-Hill.
Cita Chicago Style (17a ed.)Ries Al y Jack Trout. Positioning: The Battle for Your Mind. 20th anniversary edition. New York: McGraw-Hill, 2001.
Cita MLA (9a ed.)Ries Al y Jack Trout. Positioning: The Battle for Your Mind. 20th anniversary edition. McGraw-Hill, 2001.
Precaución: Estas citas no son 100% exactas.