diff --git a/docs/10-about.md b/docs/10-about.md
index 2b9fb9e..6653de7 100644
--- a/docs/10-about.md
+++ b/docs/10-about.md
@@ -33,8 +33,8 @@ hash links in the footer of various pages and the content is licensed for free
 distribution and, in some cases, modification.)
 
 
-[0] http://www.gnu.org/philosophy/
-[1] http://www.gnu.org/philosophy/words-to-avoid.html#Hacker
-[2] http://gnu.org/
-[3] http://eff.org/
+[0]: http://www.gnu.org/philosophy/
+[1]: http://www.gnu.org/philosophy/words-to-avoid.html#Hacker
+[2]: http://gnu.org/
+[3]: http://eff.org/
 [easejs]: https://gnu.org/software/easejs
diff --git a/docs/20-projects.md b/docs/20-projects.md
index f937353..d88d53d 100644
--- a/docs/20-projects.md
+++ b/docs/20-projects.md
@@ -35,9 +35,9 @@ screen][6] back to life by cleaning up the code, bringing it up to date, dumping
 some cruft, and adding exciting new features.
 
 
-[0] https://gitlab.com/u/mikegerwitz/
-[2] https://www.gnu.org/software/easejs
-[3] https://gitorious.org/repo2html
-[4] https://gitlab.com/mikegerwitz/git-supp
-[5] https://gitlab.com/mikegerwitz/thoughts
-[6] https://github.com/amade/screen/tree/devel
+[0]: https://gitlab.com/u/mikegerwitz/
+[2]: https://www.gnu.org/software/easejs
+[3]: https://gitorious.org/repo2html
+[4]: https://gitlab.com/mikegerwitz/git-supp
+[5]: https://gitlab.com/mikegerwitz/thoughts
+[6]: https://github.com/amade/screen/tree/devel