Update readme (#99)

* Update README.md

Add a reference to the official documentation

* Update README.md

README.md

@@ -2,6 +2,10 @@
 
 This repository hosts multiple modules related to migration and upgrade of Azure Load Balancers and Public IPs.
 
+## Upgrade a basic load balancer with PowerShell Official documentation
+
+Reference to the official documentation: [Upgrade a basic load balancer with PowerShell](https://learn.microsoft.com/en-us/azure/load-balancer/upgrade-basic-standard-with-powershell)
+
 ## Azure Basic Load Balancer Upgrade
 
 This module migrates a Basic SKU Load Balancer to a Standard SKU Load Balancer. See [Azure Basic Load Balancer Upgrade](AzureBasicLoadBalancerUpgrade/README.md)
@@ -34,4 +38,4 @@ This project may contain trademarks or logos for projects, products, or services
 trademarks or logos is subject to and must follow
 [Microsoft's Trademark & Brand Guidelines](https://www.microsoft.com/en-us/legal/intellectualproperty/trademarks/usage/general).
 Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship.
-Any use of third-party trademarks or logos are subject to those third-party's policies.
+Any use of third-party trademarks or logos are subject to those third-party's policies.