diff --git a/Doc/library/string.rst b/Doc/library/string.rst
index d935419..b27782f 100644
--- a/Doc/library/string.rst
+++ b/Doc/library/string.rst
@@ -386,8 +386,8 @@
 conversion.  The alternate form is defined differently for different
 types.  This option is only valid for integer, float and complex
 types. For integers, when binary, octal, or hexadecimal output
-is used, this option adds the prefix respective ``'0b'``, ``'0o'``, or
-``'0x'`` to the output value. For float and complex the
+is used, this option adds the respective prefix ``'0b'``, ``'0o'``,
+``'0x'``, or ``'0X'`` to the output value. For float and complex the
 alternate form causes the result of the conversion to always contain a
 decimal-point character, even if no digits follow it. Normally, a
 decimal-point character appears in the result of these conversions
@@ -467,6 +467,8 @@
    +---------+----------------------------------------------------------+
    | ``'X'`` | Hex format. Outputs the number in base 16, using         |
    |         | upper-case letters for the digits above 9.               |
+   |         | In case ``'#'`` is specified, the prefix ``'0x'`` will   |
+   |         | be upper-cased to ``'0X'`` as well.                      |
    +---------+----------------------------------------------------------+
    | ``'n'`` | Number. This is the same as ``'d'``, except that it uses |
    |         | the current locale setting to insert the appropriate     |