diff --git a/src/freedombone-adduser b/src/freedombone-adduser
index 4a61f6e7..334e518d 100755
--- a/src/freedombone-adduser
+++ b/src/freedombone-adduser
@@ -32,14 +32,14 @@ fi
 
 if [ "$SSH_PUBLIC_KEY" ]; then
     if [ ${#SSH_PUBLIC_KEY} -gt 5 ]; then
-        if [ -f $SSH_PUBLIC_KEY ]; then
+        if [ -f "$SSH_PUBLIC_KEY" ]; then
             mkdir /home/$MY_USERNAME/.ssh
             cp $SSH_PUBLIC_KEY /home/$MY_USERNAME/.ssh/authorized_keys
             echo 'ssh public key installed'
         else
-            if [[ $SSH_PUBLIC_KEY == "ssh-"* ]]; then
+            if [[ "$SSH_PUBLIC_KEY" == "ssh-"* ]]; then
                 mkdir /home/$MY_USERNAME/.ssh
-                echo $SSH_PUBLIC_KEY > /home/$MY_USERNAME/.ssh/authorized_keys
+                echo "$SSH_PUBLIC_KEY" > /home/$MY_USERNAME/.ssh/authorized_keys
                 echo 'ssh public key installed'
             else
                 echo 'The second parameter does not look like an ssh key'