TY  - JOUR 
T1  - New field observations on the competitive displacement between two species of planorbid snails inhabiting Northeastern Brasil
JO  - Memórias do Instituto Oswaldo Cruz
A1  - Barbosa, F. S.
A1  - Costa, D. P. Pereira da
A1  - Arruda, F.
SN  - 0074-0276
UL  - 10.1590/S0074-02761981000400004
VL  - 76 
Y1  - 1981
PB  - Brasil 
ER  -