diff --git a/core-java/src/test/java/com/baeldung/list/listoflist/ListOfListsTest.java b/core-java/src/test/java/com/baeldung/list/listoflist/ListOfListsTest.java
index ce24ff24bc..674a2f89bc 100644
--- a/core-java/src/test/java/com/baeldung/list/listoflist/ListOfListsTest.java
+++ b/core-java/src/test/java/com/baeldung/list/listoflist/ListOfListsTest.java
@@ -39,7 +39,8 @@ public class ListOfListsTest {
     @SuppressWarnings("unchecked")
     @Test
     public void givenListOfLists_whenRemovingElements_thenCheckNames() {
-        ((ArrayList<Pencil>) listOfLists.get(1)).remove(0);        
+
+        ((ArrayList<Pencil>) listOfLists.get(1)).remove(0);
         listOfLists.remove(1);
         assertEquals("Rubber 1", ((Rubber) listOfLists.get(1)
             .get(0)).getName());
@@ -47,4 +48,29 @@ public class ListOfListsTest {
         assertEquals("Rubber 1", ((Rubber) listOfLists.get(0)
             .get(0)).getName());
     }
+
+    @Test
+    public void givenThreeList_whenCombineIntoOneList_thenCheckList() {
+        ArrayList<Pen> pens = new ArrayList<>();
+        pens.add(new Pen("Pen 1"));
+        pens.add(new Pen("Pen 2"));
+        ArrayList<Pencil> pencils = new ArrayList<>();
+        pencils.add(new Pencil("Pencil 1"));
+        pencils.add(new Pencil("Pencil 2"));
+        ArrayList<Rubber> rubbers = new ArrayList<>();
+        rubbers.add(new Rubber("Rubber 1"));
+        rubbers.add(new Rubber("Rubber 2"));
+        
+        List<ArrayList<? extends Stationery>> list = new ArrayList<ArrayList<? extends Stationery>>();
+        list.add(pens);
+        list.add(pencils);
+        list.add(rubbers);
+        
+        assertEquals("Pen 1", ((Pen) list.get(0)
+            .get(0)).getName());
+        assertEquals("Pencil 1", ((Pencil) list.get(1)
+            .get(0)).getName());
+        assertEquals("Rubber 1", ((Rubber) list.get(2)
+            .get(0)).getName());
+    }
 }