diff --git a/doc/api/crypto.rst b/doc/api/crypto.rst
index b360e89..162e578 100644
--- a/doc/api/crypto.rst
+++ b/doc/api/crypto.rst
@@ -257,7 +257,7 @@
     Return the signature algorithm used in the certificate.  If the algorithm is
     undefined, raise :py:data:`ValueError`.
 
-    ..versionadded:: 0.13
+    .. versionadded:: 0.13
 
 
 .. py:method:: X509.get_subject()