Rao, G V S and Johansen, C and Rao, J V D K K and Jana , M K (1990) Response of the Pigeonpea-Rhizobium symbiosis to salinity stress: variation among Rhizobium strains in symbiotic ability. Biology and Fertility of Soils, 9 (1). pp. 49-53. ISSN 0178-2762