1. Burris R H 1977 Overview of nitrogen fixation.In Genetic Engineering for Nitrogen Fixation. Ed. A. Hollaender, pp 9–18, Plenum, New York.
2. Burris R H, Okon Y and Albrecht S L 1978 Properties and reactions ofSpirillum lipoferum. In Environmental Role of Nitrogen fixing Bluegreen algae and Asymbiotic Bacteria. Ecol. Bull. Stockholm 26, 353–363.
3. Dobereiner J and Day J M 1976 Associative symbioses in tropical grasses: characterization of microorganisms and dinitrogen fixing sites.In Proceedings of the 1st international symposium on nitrogen fixation. Eds. W E Newton and C J Nyman, pp 518–538, Washington, State University, Pullman.
4. Dobereiner J and Baldani V L D 1981 Prospects for inoculation of grasses withAzospirillum sp.In Associative Dinitrogen Fixation. Eds. P Vose and A P Ruschel. CRC, West Palm Beach.
5. Kapulnik Y, Sarig S, Nur I, Okon Y, Kigel J and Henis Y 1981 Yield increases in summer cereal crops in Israeli fields inoculated with Azospirillum. Exp. Agric. 17, 179–187.