Update README.md

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Author: compops

README.md

@@ -4,7 +4,7 @@ This code was downloaded from https://github.com/compops/pmh-tutorial and contai
 
 J. Dahlin and T. B. Schön, **Getting started with particle Metropolis-Hastings for inference in nonlinear models**. Pre-print, arXiv:1511:01707, 2017. 
 
-The papers are available as a preprint from http://arxiv.org/pdf/1511.01707
+The tutorial is available as a preprint from http://arxiv.org/pdf/1511.01707. An R package is also provided on CRAN with the implementation of the turorial in R. The source code (almost identitical to the code in the subdirectory R/) is found at https://github.com/compops/pmh-tutorial-rpkg.
 
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@@ -34,4 +34,4 @@ See *LICENSE* for more information.
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 ##############################################################################
-```
+```