Add link to R packaging slides

Author: ZedThree

course.md

@@ -123,7 +123,7 @@ Packaging your software is one of the important steps in a software project to m
 
 Python users will want to register for an account on [TestPyPi](https://test.pypi.org/) and install [uv](https://docs.astral.sh/uv/getting-started/installation/).
 
-**Course materials:** [slides][packaging_slides]
+**Course materials:** [Python slides][packaging_slides], [R slides][R_packaging]
 
 ### Publishing a software paper in JOSS
 **Wednesday 15th April 2026, 1pm to 2pm, hybrid.**
@@ -208,3 +208,4 @@ We'd love to hear your (anonymous) feedback: please fill in our [feedback form][
 [joss_video]: https://york-ac-uk.zoom.us/rec/share/KQsK3YR4RGTitZrsuGJMXhCIqzd1GeGcjsmMtXOFtEO7nkEcRXBFVEcX7WkDjeia.Bzf74IFgSmsw_W2I
 
 [packaging_slides]: /slides/2026-05-06-packaging.pdf
+[R_packaging]: bit.ly/3mma-pkg