diff --git a/iterators.tex b/iterators.tex
index 95cb0c79..377162a5 100644
--- a/iterators.tex
+++ b/iterators.tex
@@ -1034,7 +1034,7 @@
     requires(I i) {
       typename difference_type_t<I>;
       requires SignedIntegral<difference_type_t<I>>;
-      { ++i } -> Same<I&>; // not required to be equality preserving
+      { ++i } -> Same<I>&; // not required to be equality preserving
       i++; // not required to be equality preserving
     };
 \end{codeblock}
@@ -1075,7 +1075,7 @@
     Regular<I> &&
     WeaklyIncrementable<I> &&
     requires(I i) {
-      { i++ } -> Same<I>;
+      { i++ } -> Same<I>&&;
     };
 \end{codeblock}
 
@@ -1172,8 +1172,8 @@
     Sentinel<S, I> &&
     !disable_sized_sentinel<remove_cv_t<S>, remove_cv_t<I>> &&
     requires(const I& i, const S& s) {
-      { s - i } -> Same<difference_type_t<I>>;
-      { i - s } -> Same<difference_type_t<I>>;
+      { s - i } -> Same<difference_type_t<I>>&&;
+      { i - s } -> Same<difference_type_t<I>>&&;
     };
 \end{itemdecl}
 
@@ -1331,8 +1331,8 @@
     ForwardIterator<I> &&
     DerivedFrom<iterator_category_t<I>, bidirectional_iterator_tag> &&
     requires(I i) {
-      { @\dcr@i } -> Same<I&>;
-      { i@\dcr@ } -> Same<I>;
+      { --i } -> Same<I>&;
+      { i-- } -> Same<I>&&;
     };
 \end{codeblock}
 
@@ -1372,12 +1372,13 @@
     StrictTotallyOrdered<I> &&
     SizedSentinel<I, I> &&
     requires(I i, const I j, const difference_type_t<I> n) {
-      { i += n } -> Same<I&>;
-      { j + n } -> Same<I>;
-      { n + j } -> Same<I>;
-      { i -= n } -> Same<I&>;
-      { j - n } -> Same<I>;
-      { j[n] } -> Same<reference_t<I>>;
+      { i += n } -> Same<I>&;
+      { j + n }  -> Same<I>&&;
+      { n + j }  -> Same<I>&&;
+      { i -= n } -> Same<I>&;
+      { j - n }  -> Same<I>&&;
+      j[n];
+      requires Same<decltype(j[n]), reference_t<I>>;
     };
 \end{codeblock}
 
diff --git a/numerics.tex b/numerics.tex
index b5e33169..e828359f 100644
--- a/numerics.tex
+++ b/numerics.tex
@@ -22,10 +22,11 @@
 namespace std { namespace experimental { namespace ranges { inline namespace v1 {
   template <class G>
   concept bool UniformRandomNumberGenerator =
-    requires(G g) {
-      { g() } -> UnsignedIntegral; // not required to be equality preserving
-      { G::min() } -> Same<result_of_t<G&()>>;
-      { G::max() } -> Same<result_of_t<G&()>>;
+    Invocable<G&> &&
+    UnsignedIntegral<result_of_t<G&()>> &&
+    requires {
+      { G::min() } -> Same<result_of_t<G&()>>&&;
+      { G::max() } -> Same<result_of_t<G&()>>&&;
     };
 }}}}
 \end{codeblock}