Using-Fidle/Linux-installation-with-pip.md

@@ -52,7 +52,7 @@ $ source ./fidle-env/bin/activate
 We can now install all the necessary modules in our python environment :
 
 ```plaintext
-(fidle-env) $ pip install --index-url https://download.pytorch.org/whl/cpu \
+(fidle-env) $ pip install --extra-index-url https://download.pytorch.org/whl/cpu \
                           torch             \
                           torchvision       \
                           torch-geometric   \