Dyfyniad APA

(1974). Helical springs / prepared by the Spring Research Association.

Dyfyniad Arddull Chicago

Helical Springs / Prepared by the Spring Research Association. 1974.

Dyfyniad MLA

Helical Springs / Prepared by the Spring Research Association. 1974.

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