1. Okon, Y. and Vanderleyden, J., Root-Associated Azospirillum Species Can Stimulate Plants, ASM News, 1997, vol. 63, pp. 366–370.
2. Konnova, S.A., Skvortsov, I.M., Makarov, O.E., and Ignatov, V.V., Characteristics of the Polysaccharide Complexes Produced by Azospirillum brasilense and of the Polysaccharides Derived from Them, Mikrobiologiya, 1994, vol. 63, no. 6, pp. 1020–1030.
3. Xie, C.H. and Yokota, A., Azospirillum oryzae sp. nov., a Nitrogen-Fixing Bacterium Isolated from the Roots of the Rice Plant Oryza sativa, Int. Syst. Evol. Microbiol., 2005, vol. 55, pp. 1435–1438.
4. Peng, G., Wang, H., Zhang, G., Hou, W., Liu, Y., Wang, E.T., and Tan, Z., Azospirillum melinis sp. nov., a Group of Diazotrophs Isolated from Tropical Molasses Grass, Int J. Syst. Evol. Microbiol., 2006, vol. 56, pp. 1263–1271.
5. Mehnaz, S., Weselowski, B., and Lazarovits, G., Azospirillum canadense sp. nov., a Nitrogen-Fixing Bacterium Isolated from Corn Rhizosphere, Int. J. Syst. Evol. Microbiol., 2007, vol. 57, no. 3, pp. 620–624.