diff --git a/README.md b/README.md
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+# C++ paper for addition of `mdspan.at()`
+
+## Prepare
+
+```sh
+make update
+```
+
+See also [github.com/mpark/wg21](https://github.com/mpark/wg21/blob/master/README.md).
+
+## Build
+
+### HTML
+
+```sh
+make html
+open generated/paper.html
+```
+
+### PDF
+
+```sh
+make pdf
+open generated/paper.pdf
+```
diff --git a/wg21 b/wg21
index 266f721..0c965d0 160000
--- a/wg21
+++ b/wg21
@@ -1 +1 @@
-Subproject commit 266f72191a60f10f5670b49cd6cf5ff2134b71ad
+Subproject commit 0c965d0d7bb71b66401b324f655ad881063e16d3