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@@ -53,6 +53,7 @@ In this repository, you'll find codes for Data Structure Lab.
 1. [Unit 1 - Introduction to Algorithm and Data Structures](https://git.kska.io/sppu-se-comp-codes/DSL/src/branch/main/notes/Unit%201)
 2. [Unit 2 - Linear Data Structure Using Sequential Organization](https://git.kska.io/sppu-se-comp-codes/DSL/src/branch/main/notes/Unit%202)
 3. [Unit 3 - Searching and Sorting](https://git.kska.io/sppu-se-comp-codes/DSL/src/branch/main/notes/Unit%203)
+4. [Unit 4 - Linked List](https://git.kska.io/sppu-se-comp-codes/DSL/src/branch/main/notes/Unit%204)
 
 ### [Question Bank](https://git.kska.io/sppu-se-comp-codes/DSL/src/branch/main/notes/FDS%20-%20Question%20Bank%20%28Unit%201-6%29.pdf)