TREWARTHA, G. T., ROBINSON, A. H., & HAMMOND, E. H. (1967). Elements of geography: Physical and culture.-- ed.5. McGraw-Hill Book co.
Dyfyniad Arddull ChicagoTREWARTHA, Glenn T., Arthur H. ROBINSON, and Edwin H. HAMMOND. Elements of Geography: Physical and Culture.-- Ed.5. New York: McGraw-Hill Book co, 1967.
Dyfyniad MLATREWARTHA, Glenn T., et al. Elements of Geography: Physical and Culture.-- Ed.5. McGraw-Hill Book co, 1967.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.