Merge pull request bizz84#265 from bizz84/feature/link-testing-autore…

…newable-subscriptions

README.md

@@ -516,6 +516,7 @@ Note that the pre-registered in app purchases in the demo apps are for illustrat
 * [objc.io - Receipt Validation](https://www.objc.io/issues/17-security/receipt-validation/)
 * [Apple TN 2413 - Why are my product identifiers being returned in the invalidProductIdentifiers array?](https://developer.apple.com/library/content/technotes/tn2413/_index.html#//apple_ref/doc/uid/DTS40016228-CH1-TROUBLESHOOTING-WHY_ARE_MY_PRODUCT_IDENTIFIERS_BEING_RETURNED_IN_THE_INVALIDPRODUCTIDENTIFIERS_ARRAY_)
 * [Invalid Product IDs](http://troybrant.net/blog/2010/01/invalid-product-ids/): Checklist of common mistakes
+* [Testing Auto-Renewable Subscriptions on iOS](http://davidbarnard.com/post/164337147440/testing-auto-renewable-subscriptions-on-ios)
 
 I have also written about building SwiftyStoreKit on Medium: