Παραπομπή APA

Spekke, A. A., & Rockefeller, N. A. (1975). The next 25 years: Crisis & opportunity. Washington, D.C: World Future Society.

Παραπομπή Chicago Style

Spekke, Andrew A., and Nelson A. Rockefeller. The Next 25 Years: Crisis & Opportunity. Washington, D.C: World Future Society, 1975.

Παραπομπή MLA

Spekke, Andrew A., and Nelson A. Rockefeller. The Next 25 Years: Crisis & Opportunity. Washington, D.C: World Future Society, 1975.

Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.