Update introduction.md

docs/introduction.md

@@ -17,7 +17,7 @@ Event sourcing might be a good choice for your project if:
 - your app has auditing requirements: the reason why your app is in a certain state is equally as important as the state itself
 - you foresee that there will be a reporting need in the future, but you don't know yet which data you need to collect for those reports
 
-Some concepts in the package, for example the testing methods of aggregates, were inspired by [Frank De Jonge](https://twitter.com/frankdejonge/)'s [EventSauce] package.
+Some concepts in the package, for example the testing methods of aggregates, were inspired by [Frank De Jonge](https://twitter.com/frankdejonge/)'s [EventSauce](https://eventsauce.io/) package.
 
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