Dyfyniad APA

Britannica, E. (1981). Britannica year book of science and the future. U.S.A.

Dyfyniad Arddull Chicago

Britannica, Encyclopaedia. Britannica Year Book of Science and the Future. Chicago: U.S.A, 1981.

Dyfyniad MLA

Britannica, Encyclopaedia. Britannica Year Book of Science and the Future. U.S.A, 1981.

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