Cita APA (7th ed.)

Helmer-Hirschberg, O. (1967). Analysis of the future: The delphi method. The Rand Corporation.

Cita Chicago (17th ed.)

Helmer-Hirschberg, Olaf. Analysis of the Future: The Delphi Method. Sta. Monica, Ca: The Rand Corporation, 1967.

Cita MLA (9th ed.)

Helmer-Hirschberg, Olaf. Analysis of the Future: The Delphi Method. The Rand Corporation, 1967.