diff --git a/script/brew_core_update b/script/brew_core_update
index feed52a..4188dec 100755
--- a/script/brew_core_update
+++ b/script/brew_core_update
@@ -79,7 +79,7 @@ echo "REVISION: ${REVISION}"
 # Update Version
 #
 
-script/version_bump "${MAS_VERSION}" "$REVISION"
+script/version_bump "${MAS_VERSION}" "${REVISION}"
 
 branch_name="releases/release-${MAS_VERSION}"
 $echo git branch "${branch_name}"
diff --git a/script/version_bump b/script/version_bump
index 83ad244..7d14047 100755
--- a/script/version_bump
+++ b/script/version_bump
@@ -24,7 +24,7 @@ fi
 
 # arg 1 - version tag
 if test -n "${1}"; then
-  MAS_VERSION=${1}
+  MAS_VERSION="${1}"
 fi
 
 # arg 2 - revision (commit hash)