diff --git a/source/index.txt b/source/index.txt
index 440858d7e5a..0d1cd0cd650 100644
--- a/source/index.txt
+++ b/source/index.txt
@@ -152,7 +152,7 @@ MongoDB. You can:
   <https://www.mongodb.com/lp/whitepaper/architecture-guide?tck=docs_server>`_
 
 - Read the `Practical MongoDB Aggregations
-  <https://www.practical-mongodb-aggregations.com>` e-book__
+  <https://www.practical-mongodb-aggregations.com>`__ e-book
 
 Licensing
 ---------