Παραπομπή APA

Ravera, O. (1979). Biological aspects of freshwater pollution. Commission of the european communities.

Παραπομπή Chicago Style

Ravera, O. Biological Aspects of Freshwater Pollution. Oxford: Commission of the european communities, 1979.

Παραπομπή MLA

Ravera, O. Biological Aspects of Freshwater Pollution. Commission of the european communities, 1979.