diff --git a/sundown/LICENSE.md b/sundown/LICENSE.md
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+Sundown
+=======
+
+Source: https://github.com/vmg/sundown
+
+This file contains excerpts from the upstream readme, including the license
+terms.
+
+`Sundown` is a Markdown parser based on the original code of the
+[Upskirt library](http://fossil.instinctive.eu/libupskirt/index) by Natacha Porté.
+
+Credits
+-------
+
+`Sundown` is based on the original Upskirt parser by Natacha Porté, with many additions
+by Vicent Marti (@vmg) and contributions from the following authors:
+
+	Ben Noordhuis, Bruno Michel, Joseph Koshy, Krzysztof Kowalczyk, Samuel Bronson,
+	Shuhei Tanuma
+
+License
+-------
+
+Permission to use, copy, modify, and distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.