diff --git a/README.md b/README.md
index 814ceb6..5ed3d34 100644
--- a/README.md
+++ b/README.md
@@ -1103,7 +1103,7 @@ basename() {
     # Usage: basename "path" ["suffix"]
     local tmp
 
-    tmp=${1%${1##*[!/]}}
+    tmp=${1%"${1##*[!/]}"}
     tmp=${tmp##*/}
     tmp=${tmp%"${2/"$tmp"}"}
 
diff --git a/manuscript/chapter5.txt b/manuscript/chapter5.txt
index 4be6b11..09282b2 100644
--- a/manuscript/chapter5.txt
+++ b/manuscript/chapter5.txt
@@ -42,7 +42,7 @@ basename() {
     # Usage: basename "path" ["suffix"]
     local tmp
 
-    tmp=${1%${1##*[!/]}}
+    tmp=${1%"${1##*[!/]}"}
     tmp=${tmp##*/}
     tmp=${tmp%"${2/"$tmp"}"}