diff --git a/db/computer_networks.md b/db/computer_networks.md
index 7294294..350cc32 100644
--- a/db/computer_networks.md
+++ b/db/computer_networks.md
@@ -5,6 +5,7 @@
   
   ### Materials
 - [Wikipedia](https://en.wikipedia.org/wiki/Computer_network)
+- [ArtOfTesting - The Different types of network] (https://artoftesting.com/types-of-network)
 - [Tutorialology](https://www.tutorialology.com/computer-networking/)
 - [Tutorialspoint](https://www.tutorialspoint.com/computer_fundamentals/computer_networking.htm)
 - [Basics of Computer Networking](https://www.geeksforgeeks.org/basics-computer-networking/)
@@ -164,4 +165,4 @@
 - [Introducción a las Redes](http://www2.elo.utfsm.cl/~iwg101/ClaseRedes.pdf)
 - [Comunicaciones y Redes](https://richardfong.files.wordpress.com/2011/02/stallings-william-comunicaciones-y-redes-de-computadores.pdf)
 - [Fundamentos y Tecnologia](https://www.uv.mx/personal/artulopez/files/2012/09/08-Fun-y-Tec-de-Redes-de-C.pdf)
-</details>
\ No newline at end of file
+</details>