diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst
index 4f42217..a0849a4 100644
--- a/docs/development/test-vectors.rst
+++ b/docs/development/test-vectors.rst
@@ -103,9 +103,14 @@
 * ``utf8_common_name.pem`` - An RSA 2048 bit self-signed CA certificate
   generated using OpenSSL that contains a UTF8String common name with the value
   "We heart UTF8!™".
+
+Custom X.509 Request Vectors
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
 * ``dsa_sha1.pem`` - Contains a certificate request using 1024-bit DSA
   parameters and SHA1 generated using OpenSSL.
-* ``rsa_md4.pem`` - Contains a certificate request using 2048 bit RSA and MD4 generated using OpenSSL.
+* ``rsa_md4.pem`` - Contains a certificate request using 2048 bit RSA and MD4
+  generated using OpenSSL.
 * ``rsa_sha1.pem`` - Contains a certificate request using 2048 bit RSA and
   SHA1 generated using OpenSSL.
 * ``rsa_sha256.pem`` - Contains a certificate request using 2048 bit RSA and