Link OOB SDK partial README

README.md

@@ -12,6 +12,7 @@
   - [Update card state](#Update-card-state)
   - [Retrieve Secure Data](#Retrieve-secure-data)
   - [Push Provisioning](#Push-provisioning)
+- [Out of Band (OOB) Authentication](#Checkout Out of Band (OOB) Authentication SDK)
 - [Contact](#Contact)
 ***
 
@@ -226,6 +227,10 @@ There are some behaviors to be aware of when you attempt a push provisioning ope
   - in the sandbox Checkout.com environment, you'll receive a `pushProvisioningFailure` error, as push provisioning is only valid in production
   - in the production Checkout.com environment, you'll receive an `OperationResult` success message
 
+***
+# Checkout Out of Band (OOB) Authentication SDK
+Please find documentation [here](https://github.com/checkout/CheckoutCardManagement-iOS/blob/main/.github/partial-readmes/OOB-SDK-README.md).
+
 ***
 # Contact
 For Checkout.com issuing clients, please email [email protected] for any questions.