Convention on wetlands of international importance especially as waterfowl habitat = convetion relative aux zones humides d' imrortance internationale particulierement comme habitats des oiseaux d' eau.: proceedings of the fourth meeting of the conference of the contracting parties , Montreux, Switzerland 27 june to 4 july: proces-verbaux de la quatrieme session de la ouatrieme session de la conference des parties contractantes , Montreux, Switzerland 27 juin au 4 juillet 1990.
Έκδοση: (1992)
