diff --git a/CppCoreGuidelines.md b/CppCoreGuidelines.md
index 550c5a3..ae3c9de 100644
--- a/CppCoreGuidelines.md
+++ b/CppCoreGuidelines.md
@@ -5730,7 +5730,7 @@ After a copy `x` and `y` can be independent objects (value semantics, the way no
     X::X(const X& a)
         :p{new T[a.sz]}, sz{a.sz}
     {
-        copy(a.p, a.p + sz, a.p);
+        copy(a.p, a.p + sz, p);
     }
 
     X x;