updated text with the url.

Author: nouiz

doc/machine_learning.tex

@@ -89,8 +89,7 @@ \chapter{A Var-based PLearner: NNet}
 \chapter{Boltzmann Machines and Deep Belief Networks}
 
 The equations can be seen on
-\url{http://www.iro.umontreal.ca/~lisa/twiki/bin/view.cgi/Public/DBNEquations}
-if you have an account on LISA's TWiki.
+\url{http://www.iro.umontreal.ca/~lisa/twiki/bin/view.cgi/Public/DBNEquations}.
 
 All the code files are located in {\tt
 \$PLEARNDIR/plearn\_learners/online}.