no tildes in url. (RFC 3986)

replaced í with i in the url and it still takes me to the same place
even though my browser can interpret í, url_checker cannot do it
yet.

free-programming-books.md

@@ -364,7 +364,7 @@
 * [Digital Signal Processing For Engineers and Scientists](http://www.dspguide.com/)
 * [Digital Signal Processing For Communications](http://www.sp4comm.org/)
 * [Distributed systems for fun and profit](http://book.mixu.net/distsys/single-page.html)
-* ["DYNAMIC LINKED LIBRARIES": Paradigms of the GPL license in contemporary software](http://www.lulu.com/shop/luis-enríquez-a/dynamic-linked-libraries-paradigms-of-the-gpl-license-in-contemporary-software/ebook/product-21371318.html) - Luis A. Enríquez
+* ["DYNAMIC LINKED LIBRARIES": Paradigms of the GPL license in contemporary software](http://www.lulu.com/shop/luis-enriquez-a/dynamic-linked-libraries-paradigms-of-the-gpl-license-in-contemporary-software/ebook/product-21371318.html) - Luis A. Enríquez
 * [Flow based Programming](http://jpaulmorrison.com/fbp/#book)
 * [Foundations of Programming](http://codebetter.com/files/folders/codebetter_downloads/entry179694.aspx)
 * [Getting Real](http://gettingreal.37signals.com/)