1. General Features of Algal Growth in Sewage Oxidation Ponds;Allen,1955
2. The role of blue-green algae in nitrogen fixation in rice fields;De,1939
3. Cyanophyta;Desikachary,1959
4. Nitrogen fixation by photosynthetic organisms;Fogg;Ann. Rev. Pl. Physiol.,1956
5. Fertilization of lakes by agricultural and urban drainage;Sawyer;J. N. Eng. Water Works Assoc.,1947