1. Interaction of nitrate reductase (NR) and nitrogenase activities in maize genotypes;Baldani,1981
2. Association of Azospirillum and other diazotrophs with tropical Gramineae;Boddey,1982
3. Nitrogen fixation and denitrification by a wheat-Azospirillum association;Bothe;Experimentia Supplementum,1983
4. Techniques in Bioproductivity and Photosynthesis;Coombs,1982
5. Non-symbiotic nitrogen fixation and soil fertility;Dart,1982