diff --git a/src/ch13-02-iterators.md b/src/ch13-02-iterators.md
index 0711b44..2412cd5 100644
--- a/src/ch13-02-iterators.md
+++ b/src/ch13-02-iterators.md
@@ -335,10 +335,11 @@ fn calling_next_directly() {
 #
 #[test]
 fn using_other_iterator_trait_methods() {
-    let sum: u32 = Counter::new().zip(Counter::new().skip(1))
-                                 .map(|(a, b)| a * b)
-                                 .filter(|x| x % 3 == 0)
-                                 .sum();
+    let sum: u32 = Counter::new()
+        .zip(Counter::new().skip(1))
+        .map(|(a, b)| a * b)
+        .filter(|x| x % 3 == 0)
+        .sum();
     assert_eq!(18, sum);
 }
 ```