1 files changed, 3 insertions, 3 deletions

diff --git a/include/plist/Key.h b/include/plist/Key.h
index 3de09cf..c680f1c 100644
--- a/include/plist/Key.h
+++ b/include/plist/Key.h
@@ -33,15 +33,15 @@ class Key : public Node
 public :
     Key(Node* parent = NULL);
     Key(plist_t node, Node* parent = NULL);
-    Key(Key& s);
+    Key(const Key& s);
     Key& operator=(Key& s);
     Key(const std::string& s);
     virtual ~Key();
 
-    Node* Clone();
+    Node* Clone() const;
 
     void SetValue(const std::string& s);
-    std::string GetValue();
+    std::string GetValue() const;
 };
 
 };