1. Brunnthaler, J. - 1915 - Protococcales. In A. Pascher, Die S�sswasserflora Deutschlands, �sterreichs und der Schweiz. 5, (2): 52?205, f. 1?330.
2. Collins, F. S. - 1928 Green algae of North America. G. E. Strechert & Co. New York.
3. Croasdale, Hannah - 1956 - Freshwater algae of Alaska. I. Some desmids from the interior. Part 2: Actinotaenium, Micrasterias and Cosmarium. Trans. Amer. Micros. Soc. 75: 1?70.
4. Forest, H. S. - 1954a - Handbook of Algae. The University of Tennessee Press, Knoxville.
5. oresy H. S. - 1954b - Discussion of a portion of the Ulotrichaceae. Castenea 19: 61?75.