diff --git a/README.md b/README.md
index 6aab8ee..e8089e9 100644
--- a/README.md
+++ b/README.md
@@ -155,7 +155,7 @@ The following tags should be considered purely as proposals.  They should not be
 
     - `url` (optional) This is a url that points to the full license details for this license.
 
-    Example: <podcast:license url="https://creativecommons.org/licenses/by-nc/2.0">cc-by-nc2.0</podcast:license>
+    Example: <podcast:license url="https://creativecommons.org/licenses/by/4.0/">cc-by-4.0</podcast:license>
 
 <br>
 
diff --git a/licenseslugs.txt b/licenseslugs.txt
new file mode 100644
index 0000000..f89164b
--- /dev/null
+++ b/licenseslugs.txt
@@ -0,0 +1,23 @@
+afl-3.0  -  Academic Free License v3.0
+apache-2.0  -  Apache license 2.0
+artistic-2.0  -  Artistic license 2.0
+bsl-1.0  -  Boost Software License 1.0
+bsd-2-clause  -  BSD 2-clause "Simplified" license
+bsd-3-clause  -  BSD 3-clause "New" or "Revised" license
+bsd-3-clause-clear  -  BSD 3-clause Clear license
+cc  -  Creative Commons license family	cc
+cc0-1.0  -  Creative Commons Zero v1.0 Universal
+cc-by-4.0  -  Creative Commons Attribution 4.0
+cc-by-sa-4.0  -  Creative Commons Attribution Share Alike 4.0
+wtfpl  -  Do What The F*ck You Want To Public License
+ecl-2.0  -  Educational Community License v2.0
+epl-1.0  -  Eclipse Public License 1.0
+eupl-1.1  -  European Union Public License 1.1
+agpl-3.0  -  GNU Affero General Public License v3.0
+gpl  -  GNU General Public License family
+gpl-2.0  -  GNU General Public License v2.0
+gpl-3.0  -  GNU General Public License v3.0
+lgpl  -  GNU Lesser General Public License family
+lgpl-2.1  -  GNU Lesser General Public License v2.1
+lgpl-3.0  -  GNU Lesser General Public License v3.0
+unlicense  -  The Unlicense
\ No newline at end of file