# HG changeset patch
# User Christian Urban <christian dot urban at kcl dot ac dot uk>
# Date 1448107492 0
# Node ID 27b7af6a00e532690b1fe665a4030c0d0c77f198
# Parent  8787b77c94725a2c9c0a44d864aa1995c866d87f
updatad

diff -r 8787b77c9472 -r 27b7af6a00e5 msc-projects-15.html
--- a/msc-projects-15.html	Sat Nov 21 11:48:23 2015 +0000
+++ b/msc-projects-15.html	Sat Nov 21 12:04:52 2015 +0000
@@ -68,8 +68,7 @@
   and can &ldquo;stab you in the back&rdquo; according to
   this <A HREF="http://peterscott.github.io/2013/01/17/regular-expressions-will-stab-you-in-the-back/">blog post</A>.
   For example, if you use in <A HREF="http://www.python.org">Python</A> or 
-  in <A HREF="http://www.ruby-lang.org/en/">Ruby</A> (or also in a number of other mainstream programming languages according to this
-  <A HREF="http://www.computerbytesman.com/redos/">blog</A>) the 
+  in <A HREF="http://www.ruby-lang.org/en/">Ruby</A> (or also in a number of other mainstream programming languages) the 
   innocently looking regular expression <code>a?{28}a{28}</code> and match it, say, against the string 
   <code>aaaaaaaaaaaaaaaaaaaaaaaaaaaa</code> (that is 28 <code>a</code>s), you will soon notice that your CPU usage goes to 100%. In fact,
   Python and Ruby need approximately 30 seconds of hard work for matching this string. You can try it for yourself:
@@ -83,7 +82,7 @@
   the regular expression and string further to, say, 4,600 <code>a</code>s, then you get a <code>StackOverflowError</code> 
   potentially crashing your program. Moreover (beside the "minor" problem of being painfully slow) according to this
   <A HREF="http://www.haskell.org/haskellwiki/Regex_Posix">report</A>
-  nearly all POSIX regular expression matchers are actually buggy.
+  nearly all regular expression matchers using the POSIX rules are actually buggy.
   </p>
 
   <p>
@@ -124,7 +123,8 @@
   <p>
   <B>Literature:</B> 
   The place to start with this project is obviously this
-  <A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/ppdp12-part-deriv-sub-match.pdf">paper</A>.
+  <A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/regex-parsing-derivatives.pdf">paper</A>
+  and this <A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/ppdp12-part-deriv-sub-match.pdf">one</A>.
   Traditional methods for regular expression matching are explained
   in the Wikipedia articles 
   <A HREF="http://en.wikipedia.org/wiki/DFA_minimization">here</A> and 
@@ -621,7 +621,7 @@
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