Trends and characteristics of international migration since 1950.

Manylion Llyfryddiaeth
Awdur Corfforaethol:	United Nations. Dept. of Economic and Social Affairs
Fformat:	Llyfr
Iaith:	English
Cyhoeddwyd:	New York United Nations 1979.
Cyfres:	Demographic [i.e. Population] studies no. 64
Pynciau:	Emigration and immigration > Statistics.