diff --git a/Works-in-progress.md b/Works-in-progress.md
index 9385b1a..b919230 100644
--- a/Works-in-progress.md
+++ b/Works-in-progress.md
@@ -17,7 +17,6 @@
         - [ ] `includes`
         - [ ] `equal`
         - [ ] `lexicographical_compare` (using 3-way comparisons)
-        - [ ] `includes`
         - [ ] `begin` and `end`
 - Datastructures
     - [ ] `flat_tree`