Fix reference in ModelAdmin.ordering docs.

docs/conf.py

@@ -51,6 +51,7 @@ os.environ['DATABASE_ENGINE'] = 'django.db.backends.sqlite3'
 # ones.
 extensions = [
     'sphinx.ext.autodoc',
+    'sphinx.ext.intersphinx',
 ]
 
 if not on_rtd:
@@ -128,6 +129,11 @@ pygments_style = 'sphinx'
 spelling_lang = 'en_GB'
 spelling_word_list_filename='spelling_wordlist.txt'
 
+# sphinx.ext.intersphinx settings
+intersphinx_mapping = {
+    'django': ('https://docs.djangoproject.com/en/stable/', 'https://docs.djangoproject.com/en/stable/_objects/')
+}
+
 
 # -- Options for HTML output ----------------------------------------------
 

docs/reference/contrib/modeladmin/indexview.rst

@@ -304,7 +304,7 @@ your project is using, and without any additional setup or configuration.
 ---------------------------
 
 **Expected value**: A list or tuple in the same format as a model’s
-[``ordering``](https://docs.djangoproject.com/en/stable/ref/contrib/admin/#django.contrib.admin.ModelAdmin.list_display) parameter.
+:attr:`~django.db.models.Options.ordering` parameter.
 
 Set ``ordering`` to specify the default ordering of objects when listed by
 IndexView.  If not provided, the model’s default ordering will be respected.