Dyfyniad APA

Clarke, A. C. (1984). Profiles of the future: An inquiry into the limits of the possible. New York: Holt.

Dyfyniad Arddull Chicago

Clarke, Arthur C. Profiles of the Future: An Inquiry Into the Limits of the Possible. New York: Holt, 1984.

Dyfyniad MLA

Clarke, Arthur C. Profiles of the Future: An Inquiry Into the Limits of the Possible. New York: Holt, 1984.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.