Cambridge University Press. (1941). Geological Magazine, Vol.78, (1-6).
Dyfyniad Arddull ChicagoCambridge University Press. Geological Magazine, Vol.78, (1-6). Cambridge University Press, 1941.
Dyfyniad MLACambridge University Press. Geological Magazine, Vol.78, (1-6). 1941.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.