00395nam a2200145Ia 4500008004100000020001500041082001600056100001600072245004200088260004800130300000800178650002300186650001800209653002200227170901s1976    xx            000 0 und d  a0521206456  a589.7bN95S  aNutman, P.S 0aSymbiotic Nitrogen Fixation in Plants  aCambridgebCambridge University Pressc1976  a584  aBotanical sciences  aPure Sciences  aNitrogen fixation