diff --git a/README.adoc b/README.adoc
index 05a1d31..60d838e 100644
--- a/README.adoc
+++ b/README.adoc
@@ -2,6 +2,11 @@
 
 See https://github.com/twpayne/chezmoi
 
+For syntax of template rules see also:
+
+* http://masterminds.github.io/sprig/
+* https://pkg.go.dev/text/template
+
 == Initialization
 
 TODO: how to handle a new linux system correctly.