Fig. 4.3 Elodea nuttallii, Danube Delta Biosphere reserve, June 2005 (Photo: Anca Sa ˆrbu)
Fig. 4.4 Lemna minuta (the small one) and Lemna gibba L., Kis-Balaton area, Hungary (Photo:
Marco Neubert)
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A. Sa ˆrbu et al.