TY  - JOUR 
T1  - Directed mutagenesis affects recombination in Azospirillum brasilense nif genes
JO  - Genetics and Molecular Biology
A1  - Nunes, C.P.
A1  - Passaglia, L.M.P.
A1  - Schrank, A.
A1  - Schrank, I.S.
SN  - 1415-4757
UL  - 10.1590/S1415-47572000000400032
VL  - 23 
Y1  - 2000
PB  - Brasil 
ER  -