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+# Referencing Another API Specification
 
+<!-- REFBUILDER GIF/VIDEO-->
+
+## What
+
+Referencing another specification allows for cleaner and more organized code. Some use cases are as follows:
+
+* Generate API documentaion in Hubs
+* Deduplicate common structures like responses or shared parameters in Modeling
+* Test a connected API specification in Scenarios
+* Setup a mock server for an API in Prism
+
+## How
+
+1.  Choose the **source**
+
+    * This File
+
+    * This Project
+
+      * Select a **file**
+
+    * Shared/Common
+
+    * External URL
+
+      * Enter a valid **URL** to an existing specification
+
+2.  Select a **target**, if required
+
+3.  Confirm your choice. (Only required if there is a confirm button)
+
+4.  View the referenced specification by clicking the book icon
+
+---
+**Related Links**
+
+* [Reference other Sources](../hubs/ref-other-sources-hubs.md)
+* [Creating Models](../modeling/how-to-create-models.md#How-to-Create-Models-using-the-Stoplight-Modeling-Editor)
+* [Shared Parameters and Responses](../modeling/shared-params-responses.md)
+* [Contract Testing](../testing/contract-testing.md#connecting-the-spec)
+* [Setting Up a Prism Mock Server](../prism/mocking.md)