Update the docs to be more accurate
diff --git a/docs/x509/reference.rst b/docs/x509/reference.rst
index 2029c08..ac07ead 100644
--- a/docs/x509/reference.rst
+++ b/docs/x509/reference.rst
@@ -411,7 +411,10 @@
Sets the subject's public key.
- :param public_key: The subject's public key.
+ :param public_key: The subject's public key. This can be one of
+ :class:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPublicKey`,
+ :class:`~cryptography.hazmat.primitives.asymmetric.dsa.DSAPublicKey` or
+ :class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurvePublicKey`
.. method:: serial_number(serial_number)
@@ -448,8 +451,9 @@
Adds an X.509 extension to the certificate.
- :param extension: The :class:`~cryptography.x509.Extension` to add to
- the certificate.
+ :param extension: The extension to add to the certificate. Can be one
+ of :class:`~cryptography.x509.BasicConstraints` or
+ :class:`~cryptography.x509.SubjectAlternativeName`.
.. method:: sign(backend, private_key, algorithm)