cmark

diff --git a/spec.txt b/spec.txt
@@ -4,6 +4,7 @@ author:
 - John MacFarlane
 version: 0.13
 date: 2014-12-10
+license: '[CC-BY-SA 4.0](http://creativecommons.org/licenses/by-sa/4.0/)'
 ...
 
 # Introduction

diff --git a/template.html b/template.html
@@ -68,6 +68,8 @@ a.footnoteRef > sup {
   vertical-align: baseline;
   font-size: 100%;
 }
+footer { font-size: 82%; text-align: center; margin-top: 1em;
+    margin-bottom: 1em; }
 </style>
 <script src="//code.jquery.com/jquery-1.11.0.min.js"></script>
 <script type="text/javascript">
@@ -95,10 +97,40 @@ $endif$
 <div class="authors">
 $for(author)$<span class="author">$author$</span>$sep$; $endfor$
 </div>
+<div class="license">
+<a rel="license"
+   href="http://creativecommons.org/licenses/by-sa/4.0/"><img alt="Creative
+   Commons BY-SA" style="border-width:0"
+   src="https://i.creativecommons.org/l/by-sa/4.0/80x15.png"
+   /></a><br/><span style="display:none"><span xmlns:dct="http://purl.org/dc/terms/"
+   href="http://purl.org/dc/dcmitype/Text" property="dct:title"
+   rel="dct:type">CommonMark Spec</span> by
+   <a xmlns:cc="http://creativecommons.org/ns#"
+   href="http://spec.commonmark.org" property="cc:attributionName"
+   rel="cc:attributionURL">John MacFarlane</a> is licensed under a
+   <a rel="license"
+   href="http://creativecommons.org/licenses/by-sa/4.0/">Creative
+   Commons Attribution-ShareAlike 4.0 International License</a>.</span>
+</div>
 <div id="TOC">
 $toc$
 </div>
 <div id="watermark"></div>
 $body$
+<footer>
+<a rel="license"
+   href="http://creativecommons.org/licenses/by-sa/4.0/"><img alt="Creative
+   Commons BY-SA" style="border-width:0"
+   src="https://i.creativecommons.org/l/by-sa/4.0/80x15.png"
+   /></a><br/><span xmlns:dct="http://purl.org/dc/terms/"
+   href="http://purl.org/dc/dcmitype/Text" property="dct:title"
+   rel="dct:type">CommonMark Spec</span> by
+   <a xmlns:cc="http://creativecommons.org/ns#"
+   href="http://spec.commonmark.org" property="cc:attributionName"
+   rel="cc:attributionURL">John MacFarlane</a> is licensed under a
+   <a rel="license"
+   href="http://creativecommons.org/licenses/by-sa/4.0/">Creative
+   Commons Attribution-ShareAlike 4.0 International License</a>.
+</footer>
 </body>
 </html>