diff --git a/src/lib.rs b/src/lib.rs
index 0dfa1ad..b9891c8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -46,6 +46,7 @@ impl CharExt for char {
     }
 }
 
+#[derive(Clone)]
 enum CaseMappingIter {
     Three(char, char, char),
     Two(char, char),
@@ -88,6 +89,7 @@ impl CaseMappingIter {
     }
 }
 
+#[derive(Clone)]
 pub struct ToTitlecase(CaseMappingIter);
 
 impl Iterator for ToTitlecase {