Add some more references

2016-04-03 19:39:04 -07:00
parent 24f6b246fe
commit c954a1f2b0
2 changed files with 9 additions and 0 deletions
--- a/part4/README.md
+++ b/part4/README.md
@@ -15,3 +15,7 @@ to fail; in that case, just run `elm package install` again.)
 ```bash
 elm live Main.elm --open -- --output=elm.js
 ```
+
+## References
+
+* [Union Types syntax reference](http://elm-lang.org/docs/syntax#union-types)