diff --git a/src/calibre/customize/conversion.py b/src/calibre/customize/conversion.py
index d143392749..4eae786be3 100644
--- a/src/calibre/customize/conversion.py
+++ b/src/calibre/customize/conversion.py
@@ -318,7 +318,7 @@ class OutputFormatPlugin(Plugin):
     def convert(self, oeb_book, output, input_plugin, opts, log):
         '''
         Render the contents of `oeb_book` (which is an instance of
-        :class:`calibre.ebooks.oeb.OEBBook` to the file specified by output.
+        :class:`calibre.ebooks.oeb.OEBBook`) to the file specified by output.
 
         :param output: Either a file like object or a string. If it is a string
                        it is the path to a directory that may or may not exist. The output