diff --git a/src/main/java/com/msb/iterator/v4/Main.java b/src/main/java/com/msb/iterator/v4/Main.java
index 9db4aa0..ee6ed35 100644
--- a/src/main/java/com/msb/iterator/v4/Main.java
+++ b/src/main/java/com/msb/iterator/v4/Main.java
@@ -21,7 +21,8 @@ public class Main {
 
         Iterator_ iterator = list.iterator();
         while (iterator.hashNext()) {
-            System.out.println(iterator.next());
+            Dog dog = (Dog) iterator.next();
+            System.out.println(dog);
         }
     }
 }
diff --git a/src/main/java/com/msb/iterator/v5/Main.java b/src/main/java/com/msb/iterator/v5/Main.java
index 67122d4..cde67e9 100644
--- a/src/main/java/com/msb/iterator/v5/Main.java
+++ b/src/main/java/com/msb/iterator/v5/Main.java
@@ -16,14 +16,15 @@ import com.msb.iterator.v4.Dog;
  */
 public class Main {
     public static void main(String[] args) {
-        Collection_ list = new LinkedList_();
+        Collection_<Dog> list = new LinkedList_();
         for (int i=0; i<15; i++) {
             list.add(new Dog(i));
         }
 
-        Iterator_ iterator = list.iterator();
+        Iterator_<Dog> iterator = list.iterator();
         while (iterator.hashNext()) {
-            System.out.println(iterator.next());
+            Dog dog = iterator.next();
+            System.out.println(dog);
         }
     }
 }