Remove trailing whitespace.
diff --git a/Doc/howto/regex.rst b/Doc/howto/regex.rst
index 2f085e5..4275ffb 100644
--- a/Doc/howto/regex.rst
+++ b/Doc/howto/regex.rst
@@ -1,7 +1,7 @@
 .. _regex-howto:
 
 ****************************
-  Regular Expression HOWTO  
+  Regular Expression HOWTO
 ****************************
 
 :Author: A.M. Kuchling
@@ -611,7 +611,7 @@
    is to read? ::
 
       charref = re.compile(r"""
-       &[#]		     # Start of a numeric entity reference
+       &[#]                # Start of a numeric entity reference
        (
            0[0-7]+         # Octal form
          | [0-9]+          # Decimal form
@@ -732,7 +732,7 @@
       >>> p = re.compile('\bclass\b')
       >>> print p.search('no class at all')
       None
-      >>> print p.search('\b' + 'class' + '\b')  
+      >>> print p.search('\b' + 'class' + '\b')
       <re.MatchObject instance at 80c3ee0>
 
    Second, inside a character class, where there's no use for this assertion,
@@ -1236,9 +1236,9 @@
 only report a successful match which will start at 0; if the match wouldn't
 start at zero,  :func:`match` will *not* report it. ::
 
-   >>> print re.match('super', 'superstition').span()  
+   >>> print re.match('super', 'superstition').span()
    (0, 5)
-   >>> print re.match('super', 'insuperable')    
+   >>> print re.match('super', 'insuperable')
    None
 
 On the other hand, :func:`search` will scan forward through the string,