#5478: fix copy-paste oversight in function signature.
diff --git a/Doc/library/xml.dom.rst b/Doc/library/xml.dom.rst
index 16cfad5..8a74e7d 100644
--- a/Doc/library/xml.dom.rst
+++ b/Doc/library/xml.dom.rst
@@ -611,7 +611,7 @@
    Same as equivalent method in the :class:`Document` class.
 
 
-.. method:: Element.getElementsByTagNameNS(tagName)
+.. method:: Element.getElementsByTagNameNS(namespaceURI, localName)
 
    Same as equivalent method in the :class:`Document` class.