(2002). Seventy-seventh annual report: 2001. Oxford Forestry Institute, University of Oxford.
Dyfyniad Arddull ChicagoSeventy-seventh Annual Report: 2001. Oxford Forestry Institute, University of Oxford, 2002.
Dyfyniad MLASeventy-seventh Annual Report: 2001. Oxford Forestry Institute, University of Oxford, 2002.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.