Dyfyniad APA

Gray, J. M. (2014). Geodiversity: Valuing and conserving abiotic nature (2e.). John Wiley & Sons Inc..

Dyfyniad Arddull Chicago

Gray, J. M. Geodiversity: Valuing and Conserving Abiotic Nature. 2e. Chichester, West Sussex, UK: John Wiley & Sons Inc., 2014.

Dyfyniad MLA

Gray, J. M. Geodiversity: Valuing and Conserving Abiotic Nature. 2e. John Wiley & Sons Inc., 2014.

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