Fix markup errors.
diff --git a/Doc/library/subprocess.rst b/Doc/library/subprocess.rst
index 97c0e03..b7e87ab 100644
--- a/Doc/library/subprocess.rst
+++ b/Doc/library/subprocess.rst
@@ -207,7 +207,7 @@
When *stdout* or *stderr* are pipes and *universal_newlines* is
:const:`True` then the output data is assumed to be encoded as UTF-8 and
will automatically be decoded to text. All line endings will be converted
- to ``'\n'`` as described for the universal newlines `'U'`` mode argument
+ to ``'\n'`` as described for the universal newlines ``'U'`` mode argument
to :func:`open`.
If *shell* is :const:`True`, the specified command will be executed through