Citazione Stile APA (7a Edizione)

Helmer, O. (1966). The Delphi method for systematizing judgments about the future. Univ. of California, Institute of Government and Public Affairs.

Citazione stile Chigago Style (17a edizione)

Helmer, Olaf. The Delphi Method for Systematizing Judgments About the Future. Los Angeles: Univ. of California, Institute of Government and Public Affairs, 1966.

Citatione MLA (8a ed.)

Helmer, Olaf. The Delphi Method for Systematizing Judgments About the Future. Univ. of California, Institute of Government and Public Affairs, 1966.