add Racket link

diff --git a/how_to_get_the_programming_languages_running_on_your_computer.mdwn b/how_to_get_the_programming_languages_running_on_your_computer.mdwn
index d3b44f1..1afe9b6 100644 (file)
--- a/how_to_get_the_programming_languages_running_on_your_computer.mdwn
+++ b/how_to_get_the_programming_languages_running_on_your_computer.mdwn
@@ -113,7 +113,7 @@ academic circles.
 
 Scheme itself has umpteen different "implementations", which share most of
 their fundamentals, but have slightly different extensions and interact with
-the operating system differently. One major implementation is called Racket,
+the operating system differently. One major implementation is called [Racket](http://racket-lang.org),
 and that is what we recommend you use. (A few years back they were called PLT Scheme, but then
 they changed their name to Racket.)
 If you're already using or comfortable with