APA Style
WATER erosion: abridged proceedings of the international IHP/MAB symposium on water erosion, Varna, Bulgaria, 19-24 September 1988. (1989).
:
UNESCO.
MLA Style
WATER erosion: abridged proceedings of the international IHP/MAB symposium on water erosion, Varna, Bulgaria, 19-24 September 1988.
.
:
UNESCO,
1989.
Electronic resources.