Mudannayake, C.Pain, A.2020-09-022020-09-021986Tropical Agriculturist, 142:p.11-24https://dl-doa.nsf.gov.lk/handle/1/2722NITROGEN FIXINGNitrogen fixingRhizobium speciesCowpea groupEvaluation of nitrogen fixing ability of Sri Lankan rhizobium speciesArticle