National geographic (Washington, D.C. : National Geographic Society, 1888)
v.153, no.1-6 ( Jan-Aug 1978) ; v.154, no.1-6 (Aug-Dec 1978) ; v.155, no.1-6 ( Jan-June 1979) ; v.156, no.1-6 (July-Dec 1979) ; v.157, no.1-6 ( Jan-June 1980) ; v.158, no.1-6 (july-Dec 1980)
Keywords: Geography -- Periodicals