diff --git a/README.md b/README.md
index 4adf232..ffdbee1 100644
--- a/README.md
+++ b/README.md
@@ -8,3 +8,7 @@ This repository groups all the materials I created when writing the thesis. Apar
 - The `gennet` submodule is just a quickly hacked generator of an OSPF routed network to aid in working on birdvisu.
 
 While they are added as submodules, you do not need to clone them if you are only interested in the thesis.
+Also, while they are linked here at some specific version, the "upstream"
+version (i.e. the newest version in the linked repositories) will probably be
+more up-to-date. (The link here is just for reference, I am not sure how often
+I will update it.)