Fixed TOTP test vectors.
diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst
index 97b5c34..f47f08d 100644
--- a/docs/development/test-vectors.rst
+++ b/docs/development/test-vectors.rst
@@ -58,6 +58,12 @@
* CAST5 (CBC, CFB, OFB) generated by this project.
See: :doc:`/development/custom-vectors/cast5`
+Two Factor Authentication
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+* HOTP from :rfc:`4226`
+* TOTP from :rfc:`6238` (Note that an `errata`_ for the test vectors in RFC 6238 exists)
+
Creating Test Vectors
---------------------
@@ -93,3 +99,4 @@
.. _`RIPEMD website`: http://homes.esat.kuleuven.be/~bosselae/ripemd160.html
.. _`Whirlpool website`: http://www.larc.usp.br/~pbarreto/WhirlpoolPage.html
.. _`Specification repository`: https://github.com/fernet/spec
+.. _`errata`: http://www.rfc-editor.org/errata_search.php?rfc=6238