diff --git a/CPP11.md b/CPP11.md
index 82ce077..0d92bc1 100644
--- a/CPP11.md
+++ b/CPP11.md
@@ -971,7 +971,7 @@ auto b = CountTwos(arr);  // 1
 
 ## Acknowledgements
 * [cppreference](http://en.cppreference.com/w/cpp) - especially useful for finding examples and documentation of new library features.
-* [C++ Rvalue References Explained](http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
+* [C++ Rvalue References Explained](http://web.archive.org/web/20240324121501/http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
 * [clang](http://clang.llvm.org/cxx_status.html) and [gcc](https://gcc.gnu.org/projects/cxx-status.html)'s standards support pages. Also included here are the proposals for language/library features that I used to help find a description of, what it's meant to fix, and some examples.
 * [Compiler explorer](https://godbolt.org/)
 * [Scott Meyers' Effective Modern C++](https://www.amazon.com/Effective-Modern-Specific-Ways-Improve/dp/1491903996) - highly recommended book!
diff --git a/CPP14.md b/CPP14.md
index a95ede3..f8ba613 100644
--- a/CPP14.md
+++ b/CPP14.md
@@ -202,7 +202,7 @@ See the section on [smart pointers (C++11)](README.md#smart-pointers) for more i
 
 ## Acknowledgements
 * [cppreference](http://en.cppreference.com/w/cpp) - especially useful for finding examples and documentation of new library features.
-* [C++ Rvalue References Explained](http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
+* [C++ Rvalue References Explained](http://web.archive.org/web/20240324121501/http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
 * [clang](http://clang.llvm.org/cxx_status.html) and [gcc](https://gcc.gnu.org/projects/cxx-status.html)'s standards support pages. Also included here are the proposals for language/library features that I used to help find a description of, what it's meant to fix, and some examples.
 * [Compiler explorer](https://godbolt.org/)
 * [Scott Meyers' Effective Modern C++](https://www.amazon.com/Effective-Modern-Specific-Ways-Improve/dp/1491903996) - highly recommended book!
diff --git a/CPP17.md b/CPP17.md
index ea02cf9..0e0383a 100644
--- a/CPP17.md
+++ b/CPP17.md
@@ -688,7 +688,7 @@ else { /* handle failure */ }
 
 ## Acknowledgements
 * [cppreference](http://en.cppreference.com/w/cpp) - especially useful for finding examples and documentation of new library features.
-* [C++ Rvalue References Explained](http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
+* [C++ Rvalue References Explained](http://web.archive.org/web/20240324121501/http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
 * [clang](http://clang.llvm.org/cxx_status.html) and [gcc](https://gcc.gnu.org/projects/cxx-status.html)'s standards support pages. Also included here are the proposals for language/library features that I used to help find a description of, what it's meant to fix, and some examples.
 * [Compiler explorer](https://godbolt.org/)
 * [Scott Meyers' Effective Modern C++](https://www.amazon.com/Effective-Modern-Specific-Ways-Improve/dp/1491903996) - highly recommended book!
diff --git a/CPP20.md b/CPP20.md
index f6bc070..8f85069 100644
--- a/CPP20.md
+++ b/CPP20.md
@@ -612,7 +612,7 @@ std::to_array(a); // returns `std::array<int, 3>`
 
 ## Acknowledgements
 * [cppreference](http://en.cppreference.com/w/cpp) - especially useful for finding examples and documentation of new library features.
-* [C++ Rvalue References Explained](http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
+* [C++ Rvalue References Explained](http://web.archive.org/web/20240324121501/http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
 * [clang](http://clang.llvm.org/cxx_status.html) and [gcc](https://gcc.gnu.org/projects/cxx-status.html)'s standards support pages. Also included here are the proposals for language/library features that I used to help find a description of, what it's meant to fix, and some examples.
 * [Compiler explorer](https://godbolt.org/)
 * [Scott Meyers' Effective Modern C++](https://www.amazon.com/Effective-Modern-Specific-Ways-Improve/dp/1491903996) - highly recommended book!
diff --git a/README.md b/README.md
index a5f2ee4..d9cf939 100644
--- a/README.md
+++ b/README.md
@@ -2459,7 +2459,7 @@ auto b = CountTwos(arr);  // 1
 
 ## Acknowledgements
 * [cppreference](http://en.cppreference.com/w/cpp) - especially useful for finding examples and documentation of new library features.
-* [C++ Rvalue References Explained](http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
+* [C++ Rvalue References Explained](http://web.archive.org/web/20240324121501/http://thbecker.net/articles/rvalue_references/section_01.html) - a great introduction I used to understand rvalue references, perfect forwarding, and move semantics.
 * [clang](http://clang.llvm.org/cxx_status.html) and [gcc](https://gcc.gnu.org/projects/cxx-status.html)'s standards support pages. Also included here are the proposals for language/library features that I used to help find a description of, what it's meant to fix, and some examples.
 * [Compiler explorer](https://godbolt.org/)
 * [Scott Meyers' Effective Modern C++](https://www.amazon.com/Effective-Modern-Specific-Ways-Improve/dp/1491903996) - highly recommended series of books!