diff --git a/files/exercises/4-pairing.pdf b/files/exercises/4-pairing.pdf
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diff --git a/index.html b/index.html
index 557327b..b4439f1 100644
--- a/index.html
+++ b/index.html
@@ -78,7 +78,7 @@ <h2 class="lecture-card-title"> Lecture 4: Projective Coordinates and Pairing </
                                 <ul>
                                     <li> Relations and equivalence classes. </li>
                                     <li> Projective Coordinates. </li>
-                                    <li> Adding points in projective coordinates. Scalar multiplication. </li>
+                                    <li> Adding points in projective coordinates. Scalar multiplication using double-and-add algorithm. </li>
                                     <li> Elliptic Curve Pairing. </li>
                                     <li> Pairing applications. </li>
                                 </ul>
@@ -91,10 +91,10 @@ <h2 class="lecture-card-title"> Lecture 4: Projective Coordinates and Pairing </
                     <h1 class="lecture-links-header"> <strong> Lecture Material: </strong> </h1>
 
                     <div class="lecture-links-list">
-                        <!-- <a href="files/notes/3-fields-and-ec.pdf" class="lecture-link">
+                        <a href="files/notes/4-pairing.pdf" class="lecture-link">
                             <img src="images/icons/lecture_notes_icon.png">
                             <p class="link-name"> Lecture Notes </p>
-                        </a> -->
+                        </a>
 
                         <!-- <a href="files/slides/3-ec.pdf" class="lecture-link">
                             <img src="images/icons/slides_icon.png">
@@ -106,10 +106,10 @@ <h1 class="lecture-links-header"> <strong> Lecture Material: </strong> </h1>
                             <p class="link-name"> Exercises </p>
                         </a>
 
-                        <!-- <a href="https://forms.gle/LiXaeXkzzHFyLvMX9" class="lecture-link">
+                        <a href="https://forms.gle/3Bq4DTWkp53dtdyA9" class="lecture-link">
                             <img src="images/icons/google_form.png">
                             <p class="link-name"> Test Form </p>
-                        </a> -->
+                        </a>
                     </div>
 
                     <h1 class="lecture-links-header"> <strong> Other Helpful Resources: </strong> </h1>