missing $

Change-Id: I4962fc3a9e015e3f8bb2a4de2ee1a0feb48c5ccb
diff --git a/deployment/deploy.sh b/deployment/deploy.sh
index b8d8d9c..8a3bacd 100755
--- a/deployment/deploy.sh
+++ b/deployment/deploy.sh
@@ -65,7 +65,7 @@
 }
 
 DEPLOYMENT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
-NDNCERT_DIR="$(dirname DEPLOYMENT_DIR)"
+NDNCERT_DIR="$(dirname "$DEPLOYMENT_DIR")"
 
 echo "Do you want to (re) compile and build NDNCERT? [Y/N]"
 read -r NDNCERT_COMPILE