van der Gaag, N. (1999). National and regional population trends in the European Union: Nicole van der Gaag. European Commission.
Čikaški stil citiranja (17. izdanje)van der Gaag, Nicole. National and Regional Population Trends in the European Union: Nicole Van Der Gaag. Luxembourg: European Commission, 1999.
MLA način citiranja (8. izdanje)van der Gaag, Nicole. National and Regional Population Trends in the European Union: Nicole Van Der Gaag. European Commission, 1999.
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