diff --git a/README.md b/README.md
index bfc3927..6f430f6 100644
--- a/README.md
+++ b/README.md
@@ -394,8 +394,8 @@ Mandatory.
 
 ## References
 
-* "XSD Tutorial", [Tutorials Point].
-* "XML Schema Tutorial", [W3Schools].
+* “XSD Tutorial”, [Tutorials Point].
+* “XML Schema Tutorial”, [W3Schools].
 
   [YASD]: https://gitlab.com/amlengua/apal/esquema/-/blob/main/apal.yaml
   [XSD]: https://gitlab.com/amlengua/apal/esquema/-/blob/main/apal.xsd