git submodule update Permission Denied

git submodule update

fatal: Needed a single revision

Unable to find current revision in submodule path 'cookbooks/R'

• rm -rf cookbooks/R

Permission denied (publickey)

fatal: The remote end hung up unexpectedly

• Setup Github SSH Key for this computer:  https://help.github.com/articles/generating-ssh-keys#platform-linux

REFERENCES

http://stackoverflow.com/questions/8197089/fatal-error-when-updating-submodule-using-git

https://github.com/ShareKit/ShareKit/issues/196