Cita APA (7th ed.)

RIES,TRONF. (1993). POSITIONING. MCGRAW HILL WARNER BOOKS.

Cita Chicago (17th ed.)

RIES,TRONF. POSITIONING. NEW YORK: MCGRAW HILL WARNER BOOKS, 1993.

Cita MLA (9th ed.)

RIES,TRONF. POSITIONING. MCGRAW HILL WARNER BOOKS, 1993.