diff --git a/docs/x509.rst b/docs/x509.rst
index 06a363f..d7ab647 100644
--- a/docs/x509.rst
+++ b/docs/x509.rst
@@ -527,7 +527,9 @@
             interface.
 
         :param private_key: The
-            :class:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPrivateKey`
+            :class:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPrivateKey`,
+            :class:`~cryptography.hazmat.primitives.asymmetric.dsa.DSAPrivateKey` or
+            :class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurvePrivateKey`
             that will be used to sign the request.  When the request is
             signed by a certificate authority, the private key's associated
             public key will be stored in the resulting certificate.