TY  - BOOK
AU  - Postgate,J.R.
TI  - Nitrogen fixation 
SN  - 0713126884
AV  - QR113.P6 1978 
PY  - 1978///
CY  - London
PB  - E. Arnold
KW  - Nitrogen-fixing microorganisms
KW  - Nitrogen cycle
KW  - Root-tubercles
ER  -