References
Les, D.H. 1988b. The evolution of achene morphology in Ceratophyllum (Ceratophyllaceae), III. Relationships of the "facially-spined" group. Systematic Bot. 13: 509-518. Google Scholar
Les, D.H. 1988b. The evolution of achene morphology in Ceratophyllum (Ceratophyllaceae), III. Relationships of the "facially-spined" group. Systematic Bot. 13: 509-518. Google Scholar