Reference

M. Schlangstedt, P.S. Bisen, G. Dudel, Johann Georg Kohl (1987): Interaction of Combined Nitrogen Availability and Light in the Regulation of Growth, Heterocyst Differentiation and Dinitrogen Fixation of the Planktic Blue-Green Alga Anabaena solitaria Kleb . – Archiv für Protistenkunde – 134_1987: 389 - 396.