SpringerLink (Online service) & Zhelezov, G. (2011). Sustainable development in mountain regions: Southeastern Europe. Springer Science+Business.
Chicago-viite (17. p.)SpringerLink (Online service) ja Georgi Zhelezov. Sustainable Development in Mountain Regions: Southeastern Europe. Dordrecht: Springer Science+Business, 2011.
MLA-viite (8. p.)SpringerLink (Online service) ja Georgi Zhelezov. Sustainable Development in Mountain Regions: Southeastern Europe. Springer Science+Business, 2011.
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