diff --git a/sorted.hpp b/sorted.hpp
index b9a03560..3fc4767d 100644
--- a/sorted.hpp
+++ b/sorted.hpp
@@ -42,8 +42,8 @@ class iter::impl::SortedView {
 
     // sort by comparing the elements that the iterators point to
     std::sort(std::begin(sorted_iters.get()), std::end(sorted_iters.get()),
-        [compare_func](iterator_type<Container>& it1,
-                  iterator_type<Container>& it2) {
+        [compare_func](iterator_type<Container> it1,
+                  iterator_type<Container> it2) {
           return compare_func(*it1, *it2);
         });
   }
@@ -69,8 +69,7 @@ iter::impl::SortedView<Container> iter::sorted(
 namespace iter {
   template <typename Container>
   auto sorted(Container&& container) {
-    return sorted(std::forward<Container>(container),
-        std::less<impl::iterator_deref<Container>>());
+    return sorted(std::forward<Container>(container), std::less<>{});
   }
 }