PyPI doesn't like the :RFC: role, and distutils gives the unhelpful:
$ python setup.py check --restructuredtext
running check
warning: check: Could not finish the parsing.
Using a standard link avoids this issue.
-Flexible aggregation for iCalendar feeds (:RFC:`5545`).
+Flexible aggregation for iCalendar feeds (`RFC 5545`_).
The iCalender standard provides a common format for exchanging
calendar information. This project aims to provide a library with a
.. _Google Calendar: https://support.google.com/calendar/
.. _nose: https://nose.readthedocs.org/en/latest/
.. _pytz: https://pypi.python.org/pypi/pytz/
+
+.. _RFC 5545: http://tools.ietf.org/html/rfc5545