diff --git a/index.html b/index.html
index 4f46ba3..156fc7c 100644
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+++ b/index.html
@@ -426,7 +426,7 @@ <h2 class="title is-3"><span class="dvima" id="chatgpt-for-theorem-proving">Chat
                                 <source src="images/chatgpt-2.mp4" type="video/mp4">
                             </video>
                             <div align="center">
-                                <a target="_blank" href="https://github.com/leanprover-community/mathlib/blob/32a7e535287f9c73f2e4d2aef306a39190f0b504/src/analysis/special_functions/stirling.lean#L249">Stirling’s formula</a>
+                                <a target="_blank" href="https://github.com/leanprover-community/mathlib/blob/19c869efa56bbb8b500f2724c0b77261edbfa28c/src/analysis/special_functions/stirling.lean#L252">Stirling’s formula</a>
                             </div>
                         </div>
 
@@ -435,7 +435,7 @@ <h2 class="title is-3"><span class="dvima" id="chatgpt-for-theorem-proving">Chat
                                 <source src="images/chatgpt-3.mp4" type="video/mp4">
                             </video>
                             <div align="center">
-                                <a target="_blank" href="https://github.com/leanprover-community/mathlib/blob/32a7e535287f9c73f2e4d2aef306a39190f0b504/src/algebra/big_operators/intervals.lean#L195">Gauss' summation formula</a>
+                                <a target="_blank" href="https://github.com/leanprover-community/mathlib/blob/19c869efa56bbb8b500f2724c0b77261edbfa28c/src/algebra/big_operators/intervals.lean#L195">Gauss' summation formula</a>
                             </div>
                         </div>
                     </div>