add sandbox.io link
@@ -16,7 +16,9 @@ by combining multiple bedtools operations on the UNIX command line.
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Tutorial
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-We have developed a fairly comprehensive `tutorial <http://quinlanlab.org/tutorials/bedtools/bedtools.html>`_ that demonstrates both the basics, as well as some more advanced examples of how bedtools can help you in your research. Please have a look.
+- We have developed a fairly comprehensive `tutorial <http://quinlanlab.org/tutorials/bedtools/bedtools.html>`_ that demonstrates both the basics, as well as some more advanced examples of how bedtools can help you in your research. Please have a look.
+- Robert Aboukhalil has developed `sandbox.io <https://sandbox.bio/>`_ an excellent, web-based playground for the bedtools tutorial and other widely-used genomics tools.
+
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Important notes
