APA

Helsdingen P J Van, Willemse L, . (1996). Background information on inverbrates of the habitats directive and the Bern convention. Part. III : mollusca and Echinodermata. Strasbourg: Council of Europe.

Chicago

Helsdingen P J Van, Willemse L, . 1996. Background information on inverbrates of the habitats directive and the Bern convention. Part. III : mollusca and Echinodermata. Strasbourg: Council of Europe.

Harvard

Helsdingen P J Van, Willemse L, . (1996). Background information on inverbrates of the habitats directive and the Bern convention. Part. III : mollusca and Echinodermata. Strasbourg: Council of Europe.

MLA

Helsdingen P J Van, Willemse L, . Background information on inverbrates of the habitats directive and the Bern convention. Part. III : mollusca and Echinodermata. Strasbourg: Council of Europe. 1996.