diff --git a/gambit-scheme/readme.md b/gambit-scheme/readme.md
index 4a54e09..8714400 100644
--- a/gambit-scheme/readme.md
+++ b/gambit-scheme/readme.md
@@ -9,3 +9,5 @@
 - Latest Gambit Docs: https://gambitscheme.org/latest/manual/#The-define_002dlibrary-form
 - Teach Yourself Scheme in Fixnum Days: https://docs.scheme.org/tyscheme/index-Z-H-1.html#TAG:__tex2page_toc
 - A Scheme Example library that works with r7rs: https://github.com/pseudomata/scm-example-library
+- Wikibooks: https://en.wikibooks.org/wiki/Scheme_Programming/Libraries
+- Scheme Docs: https://docs.scheme.org/