Minor doc ReST fixes.

Doc/library/pyexpat.rst

@@ -865,7 +865,7 @@ The ``errors`` module has the following attributes:
 
 .. rubric:: Footnotes
 
-.. [#] The encoding string included in XML output should conform to the
+.. [1] The encoding string included in XML output should conform to the
    appropriate standards. For example, "UTF-8" is valid, but "UTF8" is
    not. See http://www.w3.org/TR/2006/REC-xml11-20060816/#NT-EncodingDecl
    and http://www.iana.org/assignments/character-sets/character-sets.xhtml.

Doc/library/stdtypes.rst

@@ -826,7 +826,7 @@ restrictions imposed by *s*.
 
 The ``in`` and ``not in`` operations have the same priorities as the
 comparison operations. The ``+`` (concatenation) and ``*`` (repetition)
-operations have the same priority as the corresponding numeric operations.
+operations have the same priority as the corresponding numeric operations. [3]_
 
 .. index::
    triple: operations on; sequence; types

Doc/library/xml.dom.minidom.rst

@@ -247,7 +247,7 @@ utility to most DOM users.
 
 .. rubric:: Footnotes
 
-.. [#] The encoding name included in the XML output should conform to
+.. [1] The encoding name included in the XML output should conform to
    the appropriate standards. For example, "UTF-8" is valid, but
    "UTF8" is not valid in an XML document's declaration, even though
    Python accepts it as an encoding name.

Doc/library/xml.etree.elementtree.rst

@@ -1187,7 +1187,7 @@ Exceptions
 
 .. rubric:: Footnotes
 
-.. [#] The encoding string included in XML output should conform to the
+.. [1] The encoding string included in XML output should conform to the
    appropriate standards.  For example, "UTF-8" is valid, but "UTF8" is
    not.  See http://www.w3.org/TR/2006/REC-xml11-20060816/#NT-EncodingDecl
    and http://www.iana.org/assignments/character-sets/character-sets.xhtml.